A Revision of Eriogonum (Polygonaceae) Subgenus Pterogonum William J

Great Basin Naturalist

Volume 36 | Number 3 Article 3

9-30-1976 A revision of Eriogonum (Polygonaceae) subgenus Pterogonum William J. Hess The Morton Arboretum, Lisle, Illinois

James L. Reveal University of Maryland, College Park, and Smithsonian Institutuion, Washington, D.C.

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Recommended Citation Hess, William J. and Reveal, James L. (1976) "A revision of Eriogonum (Polygonaceae) subgenus Pterogonum," Great Basin Naturalist: Vol. 36 : No. 3 , Article 3. Available at: https://scholarsarchive.byu.edu/gbn/vol36/iss3/3

This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Great Basin Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. A REVISION OF ERIOGONUM (POLYGONACEAE) SUBGENUS PIEROGONUM'

William J. Hess- and James L. Reveal-^

Abstract.— This revision discusses the 10 species of Eriogonum assigned to tlie subgenus Ptero- gonum. Six of the species are essentially restricted to northern Mexico; two additional species. E. hemipteruiu and F.. nralleyi. are found primarily in Texas; and the remaining two. E. hieracifolium and E. alaluni. are the most widespread species of the subgenus being found nuunly in the Lnited States and just barely entering Mexico. The subgenus is characterized by the broad, often winged or ribbed achenes. and the generally erect liabit of the stems of these perennial herbs. Three new species, E. finibrialum, E. viscanuni, and F.. clivosum, are described. They are related to E. ciliaium and are found in the desert foothills of north central Mexico. Two new varieties of E. atrorubens are proposed. One, var. nemorosuin. is restricted to the high mountains of the Sierra Madre Occidental in northern I])urango and southern Chihuahua, while the second, var. aurilulum, is a plant of the Sierra Madre Oriental of Coahuila and Nuevo Leon. The subgenus is divided into four sections, two of which. Peregrina and Astra, are new. Cytological information is given for nearly all taxa and shows tlie majority of species to have a luii)l<)i{l number of 20. Eriogonum atrorubens var. intonsum is a polyploid with « = 'K). and E. greggii is the most unusual with a hajjloid number of 16. Each species is described in detail, discussed, and illustrated. Distribution maps are given noting the known locations for each taxon.

The genus Eriogonum Michx. (Poly- mainly with the United States species. gonaceae) is comprised of nearly 250 spe- Since 1971, however, we have worked to- cies and, perhaps, 160 varieties. It is found gether on this revision and have concen- primarily in western North America as trated our efforts in northern Mexico. far north as Alaska and southward as far Herbarium studies have been intensively as north central Mexico. It occurs in conducted in numerous institutions both numerous ecological situations, ranging in North America and in western Europe. from desert to alpine life zones. The only As a result of the present studies, we have recent published monograph is Stokes' seen nearly all entities of the subgenus (1936), and because there are no keys in the field, have reviewed the vast ma- and only brief descriptions, it is imprac- jority of extant collections, and can now tical to use. One of us (Reveal) has be- report chromosome numbers for nearly gun a study of the genus at all levels, all taxa of Pterogonum. and this joint effort is a part of that study Herbarium citations which are includ- as well as portions of our respective doc- ed in this revision follow the suggested toral dissertations. abbreviations for major herbaria as pro- During the formative years of this re- posed by Holmgren and Keuken (1974). search (1961 to 1969), each of us worked Our subgenus Pterogonum is here de- on the subgenus Pterogonum (H. Gross) fined to include those species of Eriogo- Reveal ^^^th varying degrees of concentra- num which are upright herbaceous pe- tion. For Hess (1967). this subgenus rej)- rennials with leaves covered by pilose to resented the subject of his dissertation. strigose hairs, non-jointed stems arising in which he devoted most of his efforts singly from each caudex, with or with- on field studies and an evaluation of those out cauline leaves or foliaceous bracts, species found mainly in the United States. solitary involucres which are often pe- Reveal (1969b) reviewed the entire genus dunculated, and large, strongly angled for his dissertation, and in his treatment or even winged achenes with a straight of Pterogonum, he leaned heavily upon embryo. We recognize ten species and the work of Hess (1967), and, too, w^orked eight varieties among four sections, the

^Subniitted. in part, as partial fiilfillinent for tlie doctoral degrees from the University of Oklahoma (Hess) and Brigham \oung_ University (RcvealV Support of the current research has been via Xational Science Foundation grants GB-22fi4') and BMS75-1 5nr>^ to Reveal. The public ation support lias been provided by The Morton Arboretum and the University of Mary- land .•\gririiltiire Experiment Station (' Scientific .Article No. .<\2245. Contribution No. 5235). We are grateful for the as- sistance and patience given us by our major piofessors. George J. Goodman and Stanley L. Welsh, and the critical sug- gestions on this manuscript by Marion T. Hall. I-"igurcs S+ and 55 were drawn by the staff artist of The Morton .Xrboretum, Nancy flart. .\11 other plant illustrations were drawn by Dolly Barker Woll of Mar>-land. Lastly, we are grateful for having knowni and been inspired bv the late Lloyd Shinners of Southern Methodist University, This paper is presented in nis memory. ^Associate Taxonomist. The Morton ,\rboretuni. Lisle, Illinois 60532. 'Associate Professor of Botany, University of Marv-land, College Park. Maryland 20742. and Research .Associate, National Museimi of Natural History. Smithsonian Institution. Washington. D.C. 20560.

281 282 GREAT BASIN NATURALIST Vol. 3fi, No. 3

majority of which occur in northern Section 1 A, overlooked the strength of the Mexico and southwestern United States. relationship between the two genera Erio- gonum and Pterogonum. History and Interpretations The major characteristics linking the members of our subgenus Pterogonum are Originally, Bentham (1856) placed the the ])erennial nature of the plants \Ndth a members of Eriogonum with winged single stem arising from the caudex, pe- achenes, E. alatum Torr. in Sitgr., E. hie- dunculate in^'olucres, non-stipitate flowers, rocijolium Benth. in DC, and E. atro- and a straight embryo. The precise de- rubens Engelm. in Wisliz., in a section he limitation of the sections within the sub- called Alata. Torrey and Gray (1870) genus has been debated between us, and but, in treated these species similarly ad- the differences of opinion all have some dition, placed the related species E. cilia- justification. Reveal (1969a, 1969b') recog- turn Torr. ex Benth. in DC, in section Pe- nized two sections in his early versions, dunculata and E.. greggii Torr. & Gray in while Hess (1967) felt that at least three section Pseudo-stipulata. These latter are were more reasonable. As a result of our now interpreted by Reveal (1969a) as field and cytological work, we now propose part of the subgenus Ganysma (S. Wats.j four sections within the subgenus. Includ- Greene. Watson (1877) did not recognize ed in section Pterogonum is the subsec- section Alata but instead included E. ala- tion Pterogonum, which comprises the tum and E. hieracifolium in his larger type for the subgenus, Eriogonum atro- section, Eueriogonum, and placed E. atrorubens. and its several varieties, and the rubens with E. ciliatum and E. greggii other subsection, Adenogonum Hess & in section Ganysma. Gross (1913) inter- Reveal, with E. ciliatum. E. clirosum preted the Alata group (sensu Bentham) Hess & Reveal, E. inscanum Hess & Reveal, as generically distinct from Eriogonum and E. fimbriatum Hess & Reveal, of and proposed the new genus Pterogonum which the last three named species are H. Gross to include them. Stokes (1936) new. After considerable debate, we have believed that this genus was not that dis- placed E. greggii in its own section. Pere- tinct and included E. alatum. E. hieraci- grina Hess & Reveal, acknowledging its folium. E. artorubens. E. ciliatum. and (lose superficial relationship with mem- E. greggii along with E. rupestre S. Stokes, bers of the subsection Adenogonum. The E. hemipterum (Torr. & Gray) S. Stokes, other newly proposed section, Astra Hess ' E. nealleyi Coult., and E. inflatum Torr. & Reveal, contains E. hieracifolium. E. & Frem. as Section lA of her treatment of hemipterum. and E. nealleyi. Only E. Eriogonum. Except for E. inflatum we alatum is included in Bentham's old sec- consider the species of her Section lA tion, Alata. closely related and include them in our concept of the subgenus Pterogonuni. Cytological Studies Gross's generic interpretation of Eriogo- num alatum, E. hieracifolium. and E. atro- Cvtologically, the genus Eriogonum has rubens has been endorsed by Roberty and become better understood as more counts Vautier (1964). Their treatment made no have been made and recorded. Reveal mention of any other species in Stokes's has determined numbers for numerous Section lA except for E. ciliatum. which s[)ecies, anrl we now have several counts was placed in Eriogonum and not Ptero- in nearly all subgenera. Since the first gonum. They did concede, however, that r('[)()rted counts by Stebbins (1942), a E. ciliatum was closely related to Pterogo- number of papers (far too mmierous to num. There is litle doubt that E. ciliatum. cite here) have appeared with chromo- E. greggii. E. hemipterum, and E. nealleyi some numbers for various species of the belong in the subgenus Pterogonum as genus. The counts found in Eriogonum pointed out by Reveal ('1969a), and the vary as follows: 2n 18, 22, 24, 32. 34, close relationshif) between E. rupestre and ^6," 38, 40 and 80. Stokes and Stebbins E. atrorubens has been rey)oatedly ex- (lOVV) suggested the basic chromosome pressed by se\eral workers f.Tohiistoii lunnber to be r 10. and the more recent

1944; Hess 1967; Reveal 1967a). We be- ( ounts have tended to supf)ort this. While heve that Roberty and Vautier, by not the base number of 10 has not been found, examining all the members of Stokes's the many polyploids based on a nuiltiple k September 1976 HESS, REVEAL: REVISION OF ERIOGONUM 283

of 10 would im])ly this number. Aneu- Institution. The vouchers for Hess's ploidy, which resulted in «=- 9 or 11 or counts are at the University of Oklahoma. others, certainly may have occurred. This, A summary of the chromosome counts in conjunction with other kinds of poly- and their vouchers is given in Table 1. ploidy such as autopolyploidy and allo- See Figures 1-33 for illustrations. polyj)loidy, may have resulted in various In the subsection Pterogonum (H. poly})loid chromosome numbers. Stokes Gross) Hess & Reveal, all but one variety and Stebbins indicated that if this inter- counted of Eriogonum atroruhens have pretation is correct, then hybridization the microsporocytes with 2n= 40. In var. has phiyed an imj)ortant role in the evo- intonsum Reveal, the number is 2n= 80. lution of the present-day species of Erio- In the subsection Adenogonum, no bud gonum. material was available for E. viscanum, In our studies of Pterogonum, cytolog- but E. clivosum, E. fimhriatum, and E. ical material was obtained from buds col- ciliatum have meiotic chromosome counts lected in the field by the authors either of 2/2= 40. In section Peregrina, its only = individually or together. Reveal's method species, E. greggii. has a count of 2n of preparing smears has already been re- 32. In the sections Astra and Alata, all ported (Reveal 1968a; Reveal & Styer species and varieties showed the usual 1973), and Hess followed the method counts of 2n= 40, except E. hemiptcrum described in the second of these two var. griseum I. M. Johnst., for which we papers. The voucher specimens for Re- had no bud material. veal's earlv counts of members of Ptero- As is evident, all of the species in the gonum (Reveal 1967b, 1968b) are at Utah subgenus Pterogonum whose chromosomes State University, while those document- have been counted show 2n= 40, with ing counts since 1969 (either alone or with the exception of Eriogonum atroruhens Hess) are deposited at the Smithsonian var. intonsum (2n= 80) and E. greggii

T.\BLE 1. Chromosome numbers from microsporocytes and vouchers in Eriogonum subg. Pterogo- num. Taxon Number Voucher

Sect. Pterogonum E. atroruhens 20 Reveal et al. 2757; var. atroruhens 20 Reveal et al. 2651; Reveal & Hess 3149. var. auritulum 20 Reveal et al. 2697. var. pseudociliatum 40 Reveal et al. 2735; Reveal & Hess 3013; var. intonsum Reveal & Hess 3126. var. nemorosum 20 Reveal et al. 2737; Reveal & Hess 3105; Reveal & Hess 3124. E. ciliatum 20 Reveal et al. 2612; Reveal et al. 2616. E. fimbriaturn 20 Reveal & Hess 3144. E. clivosurn 20 Reveal et al. 2664; Reveal & Hess 3143.

Sect. Peregrina E. greggii 16 Reveal et al. 2607; Reveal & Atwood 3382. Sect. Astra E. hieracifolium 20 Hess S86; Reveal & Davidse 902; Reveal & Davidse 913; Reveal & Davidse 914. E. hemipterum var. hemipterum 20 Hess 799: Reveal 8z Davidse 906. E. nealleyi 20 Hess 876; Reveal & Davidse 900; Reveal & Davidse 901. Sect. Alata E. alatum var. alatum 20 Holmgren et al. 1961; Holmgren et al. 2070; Hess 353,- Reveal & Reveal 2772; Reveal & Reveal 2944. var. mogollense 20 Hess 761; Reveal & Reveal 3225; Reveal & Reveal 3229. var. glahriusculum 20 Hess 506; Reveal & Davidse 879; Reveal & Davidse 880. 284 c;reat basin naturalist Vol. 36. No. 3

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Figs. 19-53. - Camera ludira drawings of rhroniosomt-s from microsporocvtes of Eringonum subgenus Pterogonum. sections Astra and Alata. Fig. 19. E. hicmcifolium. n=20. metaphase I; Hess 886. Fig. 20. E. hicracifolium. n = 20. telopliase I; Reveal & Davidse 902. Fig. 21. E. hieracifolium. " = 20. telophase II; Reveal & Davidse 91-1. Fig. 22. E. hemiplerum var. hemipterum. n = 20. metaphase I; Hess 799. Fig. 23. E. hempiterum var. hemipterum. « = 20, diakinesis; /?^rfflZ & Davidse 906. 24. nealleyi. Jig. £. n = 20. metaphase I- Hess 876. Fig. 25. £. nealleyi, n = 20, telophase I: /?^z;^flZ & Davidse 900. Fig. 26. £. nealleyi. n = 20. diakinesis; Reveal & Davidse 90i . Fig. 27. £. alatum var. a/a/um. « = 20. metaphase I; Hess 353. Fig. 28. £. alatum var. alatum. n = 20. telophase II; 7?e^•^oZ ff^Lfa/ & 2772. Fig. 29. E. alatum var. mogollense. n=20. metaphase I; Hess76i. Fig. 30. £. a/a- fum var. mogollense. n = 20. diakinesis; Reveal & Reveal 3225. Fig. 31. £. alatum var mogollense 20. telophase I; ^ = /?ci;?a/ & /Jerrc/ 3229. Fig. 32. E. alatum var. glabriusculum. n = 20. metaphase Hess Fig. 1; 506. 33. E. alatum var. glabriusculum. n = 20. telophase II; Reveal & Davidse 880. 286 GREAT BASIN NATURALIST Vol. 36, No. 3

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Map 1. Distribution of Eriogonum atrorubens in northern Mexico showing var. ufrorubenx (solid circles); var. aurilulum (open triangles); var. pseudociliatum (solid bo.xes); var. inlonsuni (open circles); var, riernorosurn (solid triangles); and var. rupeslre (open bo.xes).

{2n= 32) . It is easy to acce])t the ration- chromosome nimiber would generally in- ale of the octoploid chromosome number dicate a recent divergence (Stebbins for var. intonsum, for this variant quite 1974), but each taxon must be analyzed possibly owes its origin to hybridization on its own merits. Characteristics such as involving var. atrorubens and var. ncmo- growth form, flower color, pubescence, rosurn Hess & Reveal followed h\ chromo- and glaiididarness indicate to us an early some doubling. However, an e.\[)lanation divergence from the main exolutionarv for the 32 chromosomes of E. greg^ii line in Pterogonuni, and certainly tlu> loss is a little more difficult. We feel that E. of chromosomes iiiid ( hromosomal anom- greggii is the most diverged taxon in the alies could occur at any time in the evo- subgenus, and this divergence occurred lution of a species, in this case, E. greggii. at a relatively early time in the history We will discuss this in more detail in the of the group. We recognize that most au- following section. thorities would argue that an aberrant September 1976 HKSS. KKVEAL: RF.VISION OF KRIOCIONUM 287

Evolutionary relationship of and Watson (1877) associated a part of Pterogonum within Pterogonum with species now placed in Eriogonum Ganysma, and Stokes (1936) placed E. inf/atum. another member of Ganysma, Reveal (1969a) has already ventured with the species of Pterogonum. an opinion on the relationships of the Still, there are major differences be- various subgenera within Eriogonum. It tween Pterogonum and Ganysma. Of has been difficult for us to see any fimi paramount importance is the straight place of origin for Pterogonum within embryo of Pterogonum versus the curved Eriogonum. At one time one of our major embryo of Ganysma. The pubescence professors (Goodman), playing the devil's types seen in Pterogonum are not dupli- advocate, had argued for the recognition cated in Ganysma, and the peduncles are of Pterogonum as a genus in much the rather different. In Ganysma they are same fashion as we have outlined the usually short and slender and commonly group as a subgenus within Eriogonum. much finer than the associated branch If only E. (datum existed, then some justi- system. It is thought that their morpho- fication for a distinct genus could be logical origin is by a reduction of an entire made, but the other taxa in Pterogonum branching pattern, or by the extension of tie E. (datum firmly to Eriogonum. The a branching system by the formation of recent discovery of a new shrubby genus, an involucre-bearing peduncle in the axis Dedeckera Reveal & Howell (1976), re- of a branch. In Pterogonum the morpho- lated to Eriogonum, called for a fresh re- logical development of the peduncle view of the genera in the subfamily less sophisticated. In Eriogonoidoae Benth. would seem much most species of Pterogonum the peduncles suspect that Pterogonum has its We have a similar thickness when compared closest relationship with the subgenus Gan- with the branches, or only slightly less ysma, a mixture of annuals and pe- thick. Likewise, the origin of the peduncle rennials with distinctly pedunculate in- seems to be either by the suppression of volucres, yellowish to yellowish green a branching system in which a single flowers in which some approach the flower peduncle remains, or as an extension of color of certain members of Pterogonum, a bracted axil. Both conditions are evi- as well as maroonish flowers (as in Erio- dent in E. atrorubens; however, the sup- gonum preclarum Reveal, a perennial pression of the branching system seems species from Baja California del Sur, to be most obvious in E. ciliatum and E. erect that or Mexico), and stems may greggii. In E. atrorubens no striking re- not be inflated. comparing the may Upon duction can be seen except in the final two subgenera, we found certain similar- branch division, and in its var. nemoro- ities evident. sum, the inflorescence is as highly

« Eriogonum greggii is cytologically branched as any species in Ganysma. in I unique Pterogonum with n= 16. This Thus, it seems that Pterogonum followed same niuuber appears in section Gompho- it own line of development, coupling a re- I theca (Nutt.) Reveal of Ganysma, the duction of branches with a reduction in subgenus that includes E. inflatum, E. involucre-bearing peduncles, while prob- I trichopes Torr., and others (Reveal ably the opposite is true in Ganysma. 1969b). Also in Ganysma is E. galioides The flower colors in Pterogonum are I. M. Johnst., an endemic from the east shades of yellow or yellowish green or ma- coast of Baja California, Mexico, which is roon. Eriogonum (datum best illustrates superficially similar to E. greggii, most I the yellow green shade with much lighter notably in its pubescence and flower shades of yellow to even pale white in E. color. All attempts at chromosome counts nealleyi and E. clivosum. A deep lemon for E. galioides have failed. The maroonish yellow flower color is found in E. hieraci- flowers of E. preclarum are vaguely simi- folium. These shades of yellow are found lar to those of E. ciliatum. and an unusual in a number of species in Ganysma and collection which we have tentatively iden- are not restricted to any natural part of tified as E. hemipterum (see page 316). it. The completely maroon flower color At this point it is pertinent to remind so typical of some species of Pterogonum in Eriogonum, , the reader that Torrey and Gray (1870) is not found elsewhere 288 CRF.AT BASIN NATl'RALIST Vol. 36, No. 3

5 mm

iFig. 54. lTivf)lu( i;il ;uhI flnr;il pints of Kriofio/iurn. A. /'.. (itrnrubrns viir. alrorubrns, Wislizcnus s.n.; B. E. atrorubrns vjir. rufwslrr. Pririfilr 2S'); C. K. viscaitum. Lloyd t I(k D. F.. hirrncifnUiim. Hess S86; E. E. hemiplrrum var. hemiptcruru, Hess 799; F. E. neallcyi, Hess 7S6- G. /•". ulaluni var. alatum, Hess 874; H. E. olalum var ulabriusculum, Hess 507. September \976 HKSS. RF.VEAL: RF.VISION OF FRIOGONITM 289 except for the aforementioned E. preclar- characteristic in associating groups of spe- um from Baja California, Mexico. Even in cies into higher units of classification. this species the flowers are much lif^hter However, some trends may be seen which, and diffused with yellow. The cream- when used \\\xh. other features, may so- colored flowers characteristic of E. I'is- lidify certain relationships. For instance, canum and E. finilyriatum are also found the achenes of the subgenera Eriogonum in some species of Ganysma. and Oliogogonum Nutt. are narrow, some- The flower and involucre shape in the what elongated, and variously pubescent, a plants of Pterogonum are similar to those combination of characters not seen in foimd in Ganysma. However, in Pterogo- other subgenera of Eriogonum. The num the flowers and involucres are more achenes of Eucycla (Nutt.) Kuntze, Cla- consistently alike than in any one group stomyelon Gov. & Mort., Ganysma, and in Ganvsma. Figure 34 illustrates some of OregotiiiuTi (S. Wats.) Greene are all the involucres and flowers found in essentially identical, except that those of Pterogonum. In general, the teeth of the Ganysma have a somewhat more globose involucres appear less rigid and the base than most, while those of Oregonium flowers are unspecialized with respect to are often somewhat narrower than the ma- their morphology (which is most unlike jority. But in Pterogonum the achenes the species of Ganysma where some of are unique with morphology totally un- the most specialized flowers of the genus like that found elsewhere in the genus, may be seen) . Thus, in Pterogonum. except for their large size, which is evi- flower and involucre morphology are not dent in the subgenus Eriogonum and some important taxonomic characteristics as 'Species of Oligogoruim (Fig. 35). they are in some of the other groups in The fruit of Eriogonum alatum is the Eriogonum. most spectacular in that the entire body In most of Eriogonum the achene mor- of the achene is three winged. This ap- phology is not an important taxonomic jiears to us to be an advanced stage of evo- 5mm 5mm

3 mm

Fig. 35. Achene morphology of Eriogonum. A. E. alatum var. alatum., Hess 874; B. E. hieraci- lolium, Hess 886; C. E. atrorubens var. atrorubens, Muller 3382; D. E. viscanum, Lloyd 116. 290 GREAT BASIN NATURALIST Vol. 36, No. 3 lutionary development, for, in general, the No doubt the intermittent and perma- achenes of Pterogonum are only partially nent water courses have provided avenues wdnged or merely strongly ridged or for a wider distribution of some of these angled. These large, robust fruits are not species. It is interesting that there does found in other species of Eriogonum, al- seem to be a trend in which those species though their large size is approached by with the broadest winged fruits have a E. tomentosum Michx., E. longifolium wider distribution than those species with Nutt., and in certain taxa related to E. just ridged or angled margins of the fruits. umbellatum Torr. In all of these cases, The importance of the ridged or angled however, the achenes are smooth, narrow, fruits in Pterogonum is probably not and not at all winged or strongly angled. nearly as great as is the case for those More than any other feature of Ptero- species with the distinctly winged fruits. gonum, it is the nature of the achenes Most likely these non-winged species have that is most characteristic of the group. survived better in the xeric condition of The significance of the enlarged fruit in northern Mexico because of their greater the evolutionary development of Pterogo- seed size and endosperm amount and be- num can only be conjectured. Most likely cause the competition by other Eriogonum the reduced number of flowers, involucres, species has not been so great. and branches, along with the rather xeric The basis for our belief that Pterogonum environment common to most of the spe- di^'erged early wdthin the evolutionary cies of Pterogonum, may have resulted history of Eriogonum is that there are in the formation of a large, endosperm- several features conmion to members of rich fruit. An abundant endosperm sur- this taxon and not with any of the other rounding a large, straight embyro should subgenera. Reveal (1969a) has already be environmentally advantageous as a suggested that it is easy to suy)port the means of survival for plants in which relationship of all subgenera within Erio- few seeds are produced and precipitation gonum except for two, the subgenera is seasonal and scarce. Whether this fea- Eriogonum and Pterogonum. These sub- ture is "advanced" in Eriogonum. we are genera occur on the peripheral edge of not so certain, but it is specialized and the range of the genus—one to the south we think it is adaptively important. fPterogonum) and one to the east (Eriogo- Within Eriogonum the trend seems to num) . In both cases the early divergence be toward a reduction in the amount of occurred from the rest of Eriogonum when , endosperm present concomitant with a the fragmentation of the major taxonomic curved embryo and an increase in the units (and very likely even before some of seeds number per plant. Because of of the related genera) was taking place. these trends, those extant members of Pterogonum has enjoyed a long and suc- Pterogonum have most likely survived cessful period of evolution divorced from a long evolutionary history, be- and we the majority of Eriogonum, and tlie same lieve that the external seed morphology is likely true for the subgcMuis Eriogonum represents a specialized development in a as well. Those two sul)genera have existed group which is otherwise ratlier primitive. for a long time, separated from the ma- The winged or ridged condition of the jority of Eriogonum. but having retained fruit of Pterogonum function as may an many of the early characteristics of Erio- aid to seed dispersal, an adaptation im- gonum; yet they have specialized with portant in the survival of the species and unique and unusual features found only the colonization of new localities. As the within their own taxa. fruits are relatively heavy, they do not land on the ground much more than a meter away from the plant. Once the Taxonomy fruits have landed, they may be wind- F.riofionum Michx. subgenus Ptcroponum blown for some distances, particularly (H. Gross) Rovoal those with broad wings like Eriogonum I''.ri(>n<)iiuni Michx. subg. Pterogonum (H. Gross) alatum, tumbling along the ground's KcvimI. Sida -5:82. 1967. liascd on Ptrrngonum surface until they become wedged. The ir. Gross. Bot. .talirb. Syst. 4»):239. 191 S. I.ec- wings also increase the surface area of l(il\|)(>: P. atrorubcns (Engolni. in ^Visliz.) H. Crross E. alroruhrns Engolin. in ^^'isli7.., aS the fruit without adding much weight. proposed hv Robertv & Vautier, Boissiera 10: thus enabling them to float more easily. 107. 1954. September 1976 HESS, RKVEAL: RI'AISION OF ERIOGDNIM 291

Tall erect herbaceous perennials mostly by Erio

Map 2. Distribution in iiortlieiTi Mexico of Eriogonurii cilia/uni (closecl circlos); E. fimbrintum (open box); E. viscanum (open circles); E. clivo'iurn (.solid boxes); and A', grcgpii (triangles).

stems and branches. It is most closely re- charted the results in P'igure S(i. We (hipii- lated to members of Adenogonum, as both cated the same j)roce(kires with tlie taxa groups share the broadly laminar petiole in sections Astra and Alata, again using of the basal leaves and a greatly reduced 3 5 characteristics (Fig. 37). We have at- inflorescence. However, we believe there tempted to illustrate the evolutionarN re- is ample justification for the separation lationships of thes(> taxa in the proposed of E. gregfj^ii from the other members of plnlogeneti( scheme in which two major

Adenogoiuim based on the aforomentionod lines of d(>\elopment are evident ( I*'ig-

mori)h()logi( a! distinction and the nni(]ue 5(S). In one line of evolution it would ap- chromosome number of n=16. pear tiiat subsection Adenogoniun and sec- We compared the taxa of sections tion Peregrina are apj)roximately equi- Pterogonum and Peregrina based on the distant from subsection Pterogonum but presence or absence f)f "53 characteristics. at different angles. In the other offshoot From these data we determined the per- an early dichotomy residted in the diver- centage of shared characteristics and gence of sec tioji Alata from flic other spe- Soj)t(>nihor 107(i HKSS. RKVEAL: iu:\isioN oi' i:kio(;()nuai 293 294 GKEAT BASIN NATURALIST Vol. 36, No. 3

E. a latum E. hieracifolium E. ciliatum E. greggii

E. fimbriatum

E. viscanum E. nealleyi Subsection Adenogonum

E . atrorubens

Pterogonuni Ancestor

Fig. 38. A phylogenetir scheme for the species within subgenus Petrogonum. cies in section Astra. These last two sec- specialized) feature. No other members tions differ from the former ones, pri- of the subgenus have achenes that are marily in having stems with alternately completelv winged nor even shaj)ed like arranged cauline leaves. those of E. (ilaturn, and certainly this fea- Only the widespread Eriof^nnum alatutn ture would be an advanced character over is contained wdthin the section Alata. Mor- the non-winged character. As is usual, phologically, this species is not unique ex- once a species has become established, its cept for two characteristics, monocarpy evolution proceeds along lines indepen- and distinctly winged fruits. Monocarpy dent of the pressures subjected to the other is known nowhere else in the genus Erio- ( losely related taxa. ponum. It may he appropriate, in the The three species of section Astra are determination of evolutionary relation- more restricted in distribution and occur ships, to weigh various characteristics in a more xeric habitat than Eriogonum equally; hut it is, nevertheless, most dif- alntum. Similai- to those species of sub- ficult for us to keep from emphasizing section Adenogoiunn. these taxa have also such a complex characteristic as the mono- evolved into tnore sjiecialized units, most carpic habit and the occurrence of its likcU' in response to the desert and foothill mam unknown changes. Because of the environments of northern Mexico and wide geographic range of E. alatuin. it i'exas 19'i8 for a more de - would seem that tiie moiiocar[)ic (ondition (see Axelrod In occurred early in its evolution, and. per- tailed discussion of this phenomenon). Jurraci- haps, concomitant with this adaptation it this section we charact(>rize E. was able to exploit widespread environ- fo/iurn as the central line of development, mental conditions. We belie\e the large, uith /'.'. hcrniptcrurti and E. iicdUcyi as distinctly winged fruit of A', (ilatiini is offshoots. ('ei-tainJN. the more widely another unicjue (and ()ossibly highly r-anging disti-ihution of A', hicrdcifolium September 1976 HESS, REVEAL: REVISION OF ERIOGONUM 295 in the more niesic regions and its more culum Torr. in Whipple. However, no general morphological characteristics tend direct relationship exists with var. gla- to support this suggestion. The restricted briusculum, and we believe characteristics range in xeric sites of E. hemipterum, its such as the branched caudex system, shortened inflorescences, and its smaller flower morphology, and fruit type, which maroon (or nearly so) flowers suj)port its are shared with E. hieracifolium and E. divergency from E. hicracifolium. Eriogo- hcmipterum^ are more significant. This nurn ncallcyi occurs in the most xeric species is certainly more distinctly unique habitat of all the members of Astra and re- than the others in Astra and would seem flects this condition by its convergence in to be early evolved off the E. hieracifolium appearance to E. alatum var. glahrius- line.

Map 3. Distribution of Eriogonum hieracifolium (solid circles); E. hemipterum var. hemipterum (solid triangles); E. hemipterum var. griseum (open triangles); and E. nealleyi (solid boxes). 296 GREAT BASIN NATURALIST Vol. 36, No. 3

•• •

••••

v>• •

• % ^ •. . ^ o •

-'O o

••

var. motiolh'nse Map 4. DistriljutuHi ol I'.no^ninun iilaluni showing var. aldtuni (_ solid cirrles); (open circles); and var. ulabriusculurn (solid l)oxes). vSeptember 1976 HI.SS. HF.VEAL: REVISION OF ERIOGONUM 297

Key to the Sections

Leaves strictly basal, or if a})})oariiig to he caiiline, then arranged in the axils of bracts; stems often glandular-puljescent at least at the nodes; plants mostly of Mexico. B. Leaves strictly basal, not glandular; stems erect, glabrous or glandular only at the nodes; inflorescences open, with elongated branches; flowers maroon to cream colored, glabrous or thinly pubescent I. Sect. Pterogonum BB. Leaves basal with whorled cauline leaves arranged in axils of bracts at each node, the leaf-blades glandular as well as pubescent; stems suberect or spreading, densely glandular-pubescent; inflorescences with one side suppressed, not open or with elongated branches; flowers white, densely strigose IL Sect. Peregrina

AA. Leaves basal and alternately arranged on the stem; stems glabrous to strigose, not glandular; plants mostly of the United States. B. Plants from branched caudices; achenes distinctly ribbed or winged only along the upper half; flowers deep yellow, cream white, or maroon; long-lived perennials IIL Sect. Astra BB. Plants from a deep, soft, often chambered taproot; achenes distinctly winged the entire length; flowers greenish yellow; monocarpic perennials IV. Sect. Alata

L Eriogonum sect. Pterogonum vestiture, and habitat. The subsection Pterogonum is monotypic and ranges Eriogonum Michx. subgen. Pterogonum (H. from the Mexico-Mexico line south- Gross) Reveal sect. Pterogonum. New ward to Durango mainly in the pine-oak Moderately tall, mostly erect perennial and pinyon-juniper woodlands, with an herbs, usually but not always with a single isolated population in pine woodlands in stem arising from branched caudices, gla- Zacatecas, and a major center in the high brous and glaucous, or with stipitate mountains of northeastern Mexico. These glands at or near the nodes; leaves basal, plants all have a densely branched in- oblanceolate to oblong or spathulate, gla- iFlorescence, glabrous stems and branches, brous on both surfaces except for ciliated and distinctly petiolate leaf-blades. The margins, or thinly strigose on both sur- second subsection, Adenogonum, contains faces, or tomentose below; bracts ternate. four species, three of which occur on mostly scalelike, connate at the base; g^'psum outcrops in isolated locations in inflorescences open, paniculate cATiies with north central Mexico. The majority of few to many di- and trichotomous these sites are in broken scrubland com- branches; peduncles long and usually munities often dominated b}' Larrea. These stout; involucres turbinate to campanu- plants all have highly reduced inflores- late, the (4) 5 (8) teeth acute to truncate, cences composed of only a few branches, the bractlets linear-oblanceolate, glabrous stems which are either glabrous or gland- or glandular, usually ciliolate. the pedicels ular at least at or near the nodes, and glabrous; flowers maroon, cream, or white, leaves which have broadly laminar pet- the tepals glabrous or sparsely pubsecent; ioles. Eriogonum ciliatum. the fourth spe- anthers pur])le to red or yellowdsh; cies of the subsection, is similar in aspect achenes slightly \\nnged or ridged the en- to the others except that it occurs in both tire length, glabrous. pinyon-juniper and grassland commun- The section Pterogonum is composed ities, and usually on limestone soils, and of two groups which differ primarily in has maroon instead of cream-colored the type of inflorescence development. flowers.

Key to the Subsections

Inflorescences of numerous branches, the stems reddish, glabrous, and glaucous; flowers maroon; leaves distinctly petiolate in most; wide- 298 GREAT BASIN NATURALIST Vol. 36, No. 3

spread in northern Mexico, mainly in the Sierra Madre Occidental and Oriental A. Subsect. Pterogonum

AA. Inflorescences of few branches, the stems whitish or greenish, or, if reddish, then glandular; flowers white or cream, or, if maroon, then with a bright yellow central portion within; leaves with a broadly laminar petiole; in isolated and scattered places mainly at low elevations in north central Mexico, or in the foothills of Sierra Madre Oriental of northeastern Mexico B. Subsect. Adenogonum

lA. Eriogonum subsect. Pterogonum cences open, cymose, (1.5) 3-8 dm long, the numerous branches mostly spreading, Eriogonurn Michx. sect. Pterogonum (H. Gross) Reveal subsect. Pterogonum (H. Gross) Hess trichotomously branched at the first node, & Reveal, stat. nov., based on Pterogonum H. di- or trichotomously branched above, with Gross, Bot. Jahrb. Syst. 49:239. 1913. Lecto- an involucre-bearing peduncle in the fork type: P. atrorubens (Engelm. in Wisliz.) H. of each axis, glabrous and glaucous; Gross = E. atrorubens Engelm. in Wisliz., 1-5 selected bj^ Roberty & Vautier, Boissiera 10: bracts scalelike, ternate, mm long, or 107. 1964. Tliis new status is made in accor- linear-lanceolate and 5-10 (15) mm long, dance with Article 22 of the current Interna- becoming strongly reduced in size at the tional Code of Botanical Nomenclature (Sta- uppermost nodes, sparsely pilose to stri- fleu et al. 1972). gose, especially within and along the mar- Plants tall, 4-10 (12) dm high; leaves gin, infrequently glabrous without, con- oblanceolate to elliptic or linear, 2.5-15 nate at the base; peduncles ascending to cm long, on distinct petioles in most; erect, straight or slightly curved upward- stems erect, slender and occasionally fis- ly all along their length", (1) 2-8 (12) cm tulose, glabrous and glaucous; inflores- long, glabrous; involucres solitary, tur- cences open, densely branched in most, binate to turbinate-campanulate, (1) 1.5- glabrous; flowers maroon, glabrous or 4 (4.5) mm long, 1-2.5 (3) mm wide, thinly pubescent. glabrous without, glabrous within except A monotypic group containing only for the sparsely ciliated margin with Eriogonum atrorubens. curled hairs or small glands, the (4) 5 (8) rounded or truncate or acute teeth 0.4-1.5 mm long, the bractlets linear-oblanceolate 1. Eriogonum atrorubens Engelm. to oblanceolate, 1-3.5 nmi long, glabrous in Wisliz. or ciliate and minutely glandidar, the Figs. 39, 40, & 41. pedicels 1.5-5 (6) mm long, glabrous; Tall, erect herbaceous perennials 4-10 flowers maroon to red or purple, often (12) dm high from a short, compact, with a dark green or reddish midrib, (1) branched, woody caudex; leaiH's basal, the 1.5-3 mm long in anthesis, becoming 3-6 leaf-blades linear, oblanceolate, lanceolate mm long in fruit, glabrous or strigose or oblong to elHptic, (2.5) 4-12 (15) cm without, essentially glabrous within, the long, 0.3-3 cm wide, sparsely to densely tepals essentially monomorphic, spathu- strigose on both surfaces and greenish late to oboA ate or infre(]ueiitly lanceolate, above, or densely grayish-tomentose below connate at the base; stamens slightly ex- and strigose and grayish or greenish above, serted, 1.5-5 mm long, the filaments gla- glabrous and greenish on both surfaces in brous, the anthers maroon to reddish pur- some, the margin and midribs ciliated or ple or yellowish; achenes light greenish sparsely i)ubescent, the a[)ex mostly acute brown to brown, (2) 3-5.5 nnn long, 2-3.5 to slightly obtuse, the base long cuneate mm wide, ovate, slightly 3-winged or in most, tapering gradually to an indis- ridged the entire length.

tinct petiole only in \ ar. nemorosum, the Tiifr('(]uent to locally common on ex- petiole 1-8 (12) cm long, - winged in posed meadows, grassland, and j^Iains, or some, glabrous to strigose or tomentose, in j)inyon-juniper, [)ine-oak, or pine the petiole-base strigose to villous or gla- \voo(llands, or rarely in desert scrublands, brous without, glabrous within; sterns in the Sierra Madre Occidental from ex-

erect, often solitary, 1-4.5 dm long, slen- treme Jiortherii Chihuahua and Sonora I der and sometimes fistulose at the first southward to central Durango. and in the node, glabrous and glaucous; inflores- Sierra Madre Oriental of southea.stem .

September 1976 IIESS. HI.VEAL: RF.VTSION OI'^ F.RIOGONUM 299

Coahuila and adjacent Nuevo Leon, with that the material from the Sierra Madre isolated populations near Chihuahua in Oriental probably represented another va- central Chihuahua and near Sombrerete riety (here j)roposed as var. aiiritulurn) in west central Zacatecas, Mexico, from Both of us noted the probable reduction of 1500 to 2750 m elevation (Map 1). Flow- E. rupestre to the varietal rank under E. ering mostly from Tune to October (No- ntroruhens. and this combination is hereby vember) . proposed. In our original studies, we were This species was reviewed by Reveal handicapped by a lack of field experience (1967a) at which time he proposed the with E. atroruhens. A major part of our subgeneric name Pterogonum and de- joint field effort has gone into a detailed scribed two varieties of Eriogonum atro- review of this species, and this has re- ruhpTTs. Aar. pseudociliaturn and var. in- sulted in some modification of both our tonsum. Hess (1967) essentially agreed 1967 papers. In addition, we have dis- with this treatment except to point out covered a new taxon, var. nemorosum.

Key to the Varieties of E. atroruhens

A. Flowers glabrous. B. Leaf-blades oblanceolate, lanceolate, or oblong to elliptic (2.5) 4-8 (10) cm long, (0.5) 1-3 cm wide; involucres 1.5-4 (4.5) mm long. C. Leaves glabrous or merely sparsely pubescent on both surfaces. D. Leaves pubescent at least on the lower surface, the hairs becoming sparse as the plant matures in some. E. Stems usually strongly fistulose; leaves mostly 4-8 (10) cm long; plants of Chihuahua, Sonora, and Za-

catecas - la. var. atroruhens EE. Stems not fistulose; leaves mostly 2.5-4 (6) cm long; plants of Coahuila and Nuevo Leon lb. var. auritulum DD. Leaves bright green and glabrous on both surfaces except for the ciliated margin and midvein; plants of central

Durango .- Ic. var. pspudociUatum CC. Leaves densely tomentose below, densely strigose above; plants of extreme northern Durango and adjacent southern Chihua- hua Id. var. intonsum BB. Leaf-blades lienar, (4) 6-12 (15) cm long, (0.2) 0.3-0.7 (0.9) cm wide; involucres (1) 1.5-2 (2.5) mm long; northern Durango and southern Chihuahua le. var. nemorosum

AA. Flowers strongly strigose without; plants of low desert ranges east and northeast of Chihuahua. Chihuahua If. var. rupestre

la. Eriogonum atroruhens var. more so below than above, becoming atroruhens nearly or quite glabrous in fruit; stems

Figs. 39a. b. c. d usually fistulose; involucres turbinate to turbinate-campanulate, 1.5-4 (4.5) mm Eriogonum atroruhens Engelm. in Wisliz., Mem. long, 1-2.5 (3) mm wide, the bractlets Tour North. Mex. 108. 1849.—On the banks of the streamlets at Cusihuiriarhic (originally often hirsutulous and/or glandular: Cosihuiriachi). Chihuahua, Me.xico. 19 Sep flowers glabrous; n = 20 (Figs. 1, 2). 1846. Wislizenus 172. Holotype: mo! Isotypes: Locally common in exposed grassy GH, ISC. MO. ny!—Pterngonum atroruhens meadows. f)lains. or scattered pinyon- (Engelm. in Wizliz.) H. Gross. Bot. Jahrb. foothills Syst. 49: 239. 1913. juniper woodlands on the lower and slopes of the mountains of western Plants erect, 5-10 (12) dm high; leaves Chihuahua from south central Chihuahua lanceolate or oblong to narrowly elliptic, northward in the Sierra Madre Occidental mostly 4-8 (10) cm long, 1-3 cm wide, to just south of the United States bound- strigose on both surfaces, often slightly arv in western Chihuahua and eastern 300 GREAT BASIN NATURALIST Vol. 36, No. 3

* *N

Fig. 30. Illustration of F.rioponum atrorubens showing habit of var. alrorubrns (A), a single plant in detail (B), an involucre and flowers (C), and a mature achene (D). Erioponum (ilrmubrns var. auntulum is shown in K (involucre and open flowers) and F (leaf). Kriofionuni atrorubens var. m/onsum (G) illustrates the lower surface of the leaf-blade. Eriunonurn atrorubens var. pseudo- ciliatu/n (H) illustrates the leaf-blade. Se{)toniber 1976 HESS. HLVEAL: REVISION OI'^ ERIOGONUM 301

Sonora, and in a single location northwest minute, thin, pilose hairs without; ^=20 of Sonibrerote, Zacatecas, Mexico, mostly (Figs. 3, 4). below 2150 ni elevation. Flowering from Locally infrecjuent to rather rare in June to November. heavily wooded pinyon-juniper and oak woodlands in the mountains of southeast- Represent.\tive coilections: MEXICO: Chi- ern Coahuila adjacent Leon, huahua: Cajuiichi, Rio Mayo. 3 Sep 1936, and Nuevo Gentry 2709 (ariz, gh, mo, ny, uc, us); San mainly in the Sierra Madre Oriental, Diego Canyon. 16 Sep 1903, M. E. Jones s. n. from 1,800 to 2,600 m elevation. Flower- (c.\s, Ds. MiN. MO. NY. POM. us) ; Sierra Madre, ing from May to October. 2 Oct 1887, Pringle li57 (gh. isc. min. mo, NDG, NY, uc, us); 10 mi W Cuauhtemoc. 13 Rei'rksentative COLLECTIONS: MEXICO: Coa- Aug 1971, Reveal et al. 2757 (ariz, bry, cas, huila: S of Saltillo, 25 Jul-1 Aug 1880, Palmer GH, ISC, MEXU, MICH, MO, NY, OKL, RSA, SMU. 1175 (gh, NY, p, us); Sierra Guadalupe, S of TEX, uc, UTC, WTu); 12 mi NE Zaragosa, 10 La Cuchilla, 15 Jul 1934. Pennell 1737S (ny). Sep 1972. Reveal & Hess 2986 (bry, cas. gh, Nuevo Leon: Las Canaos on Cerro Potosi, MEXU. MO. NY, UC. US, UTc). Sonora: Base of 1 Jul 1935, Mueller 218-1 (ariz, cas, gh, mo, San Luis Mts., 5 Sep 1893. Mearns 2123 (ds, NY, TEx); 1 mi S Pablillo, 6 Aug 1971. Reveal GH, NY, us). Zacatecas: 9 mi NW Sombrerete, et al. 2651 (ny, us, utc). 26 Sep 1948, Gentry H4S4 (ahfh, gh, us). The var. auritulum is morphologically The var. atroruhens. as now^ defined, similar to the montane forms of var. includes only those plants of the species atrorubens. In general, those plants of which occur principally in grassy areas in var. atrorubens have stems that are not the lower foothills of the Sierra Madre strongly inflated and occur in pinyon- Occidental and those which are found in juniper woodlands—much like the situa- open pinyon-juniper woodlands in adja- tion found in var. auritulum. However, cent mountain ranges. The plants found the latter never has inflated stems and in the grassy plains are typical of the spe- branches, the plants nearly always occur cies and may be distinguished by their under the forest canopy, and the leaves large, strigose leaves and fistulose stems are always pubescent. These minor fea- and branches. The plants which occur at tures, coupled with the strong geographi- a slightly higher elevation and in more cal separation, has led us to distinguish xeric sites usually have leaves that are not between the two. The geographical dis- as pubescent (and in fact may be nearly tance between var. auritulum and var. glabrous in fruit) and stems that are not atrorubens, which Reveal (1967a) as- as obviously inflated. sumed might be closed with more field- lb. Eriogonum atrorubens var. auritulum work, has remained distinct. The flowers of the new^ variety occasionally have what appear to be minute, Hess & Reveal sunken, whitish glands. These are usually

Fig. 39e. f seen only in fresh material, but occasionally we have noted them on dried speci- Eriogonum atrorubens Engelm. in Wisliz. var. mens. Similar glands have not been seen auritulum Hess 8z Reveal, var. nov. —A var. in the other forms of Eriogonum atro- atrorubens foliis strigosis et caulibus gracilibus differt. —Typus: Along Nuevo Leon Highway rubens. It should be noted, too, that on a 68. 13 mi S Nuevo Leon Highway 60, 3 few individual plants there are flowers mi S Pablillo. on limestone hills associated with thin pilose hairs. These hairs are not with Quercus and Pinus at about 2075 m ele- as prominent nor as abundant as those vation. Nuevo Leon, Me.vico, 18 Sep 1972, Reveal & Hess M49. Holotype: us! Isotypi: found in var. rupestre. ARIZ, BRY. CAS. GH. K. MEXU. MICH, MO, NY. TEX, UC, UTc! Ic. Eriogonum atrorubens var. Plants erect, 5-10 dm high; leaves pseudociliatum Reveal lanceolate to narrowly oblong, mostly 2.5- Fig. 39h. 4 (6) cm long, 1-3 cm wide, strigose on Eriogonum atrorubens Engelm. in Wisliz. var. both surfaces, often slightly more so below^ pseudociliatum Reveal. Sida 3:85. 1967. — Oti- than above; stems not fistulose; involucres napa NW of Ciudad Durango. Durango, turbinate, 2-3.5 mm long, 1.5-3 mm wide, Mexico, 25 Jul-5 Aug 1906, Palmer 382. Holo- type: us! Isotypes: gh. k. mo. ny, uc! the bractlets often hirsutulous and/or minutely glandular; flowers essentially Plants erect, 5-8 (10) dm high; leaves glabrous, or rarely wdth a few scattered. mostly elliptical, 4-8 (10) cm long, 1-3

kl ! —

302 GREAT BASIN NATURALIST Vol. 36, No. 3

cm wide, glabrous and bright green on (gh); Pawiciki, 13 Jul 1965. Pennington 547 both surfaces or with a few scattered hairs (tex). Durango: 5.5 mi E Ojito. 11 Aug 1971, Reveal et al. 2733 (ariz, bry, cas. gh, kans. above, the midvein and margins ciliated; KSC, MEXU, MICH, MO. NY, OKL, OSC, RM, RSA, stems usually fistulose; involucres turbi- TEX, UC, US, UTC, wtu); 1 1 mi W Ojito, 16 nate-campanulate, 2-4 mm long, 2-3 mm Sep 1972, Reveal & Hess 3126 (bry, ny, us, wide, the bractlets glabrous or glandu- utc). lar; /2 flowers glabrous; = 20. (Figs. 5, 6). Since this variant was described in Locally common in grassy meadows 1967, we have seen numerous collections, and in open pine-oak forests in the Sierra many of them gathered by ourselves. Not Madre Occidental of central Durango, suspected then was the cytological nature Mexico, 2400-2600 from m elevation. of var. intonsum. In a routine manner, Flowering from June to September. buds of var. intonsum were gathered in Representative collections: MEXICO: Duran- 1971, and counts were made during the go: 63 mi W Ciudad Durango, 28 Jun 1950. following winter. With the discovery that Maysilles 7184 (duke, ny, tex, us); El Salto. var. intonsum represented an octoploid 12 Jul 1898. Nelson 4552 (gh. us); 6.5 mi E (/2=40), we returned to the Ojito area Llano Grande. 9 Aug 1971, Reveal et al. west of del Parral, 2697 (bry, c.\s, gh. mexu, mo, ny, rsa. uc. Hidalgo and carefully

us. UTc) ; 34 mi W Ciudad Durango, 1 1 Aug searched for possible parental sources of 1956, Waterfall 12653 (ariz. tex, uc). what we came to suspect was an auto- allopolyploid origin of var. intonsum. As now defined, the var. pseudociliatum The dense tomentum associated with the nar- is restricted to the central Sierra Madre row leaves lead us to Occidental in Durango. As noted above suspect that one parent was var. under var. atrorubens. those plants of nemorosum which we had found in 1971, just to the west of var. Chihuahua previously referred to this variety by Reveal n967a) have been intonsum. A series of populations of both varieties were sampled, and var. nemoro- transferred to the typical variant. As now sum proved to be a consistent tetraploid restricted, var. pseudociliatum includes only those plants with bright green and (/2 = 20), and var. intonsum an octoploid. No chromosomal irregularities noted usually totally glabrous basal leaves. were in either taxon. However, populations of what we suspected was the other parent, Id. Eriogonum atrorubens var. var. atrorubens, could not be found in intonsum Reveal the immediate area, nor even in the foothills around Parral. Nevertheless, we still Fig. 39g. feel that var. intonsum quite possibly is of Eriogonum atrorubens Engelm. in Wisliz. var. a hybrid origin and is now a stable, self- intonsum Reveal. Sida 3: 86. 1967.—Inde, Du- reproducing taxon. rango, Mexico, Aug. 1927, Reko 5239. Holo- type: us!

Plants erect, 5-10 dm high; leaves le. Eriogonum atrorubens var. mostly narrowly elliptic to narrowly ob- nemorosum Hess & Reveal long, 4-10 (12) cm long, 1-2.5 (3) cm Fig. 40 wide, densely grayish-tomentose below, densely strigose above; stems usuallv Eriogonum atrorubens Eiipoliu. in Wisliz. var. strongly fistulose; involucres turbinate, nemorosum Hoss & Reveal, vai-. nov. —A var. 1.5-3 mm long, 1-2 mm wide, the bractlets atrorubens foliis linearihus et tonu^ntosis subra et a var. intoso foliis angustioribus differt. glabrous, hirsute, or glandular; flowers Typus: Along tlio diit road fioin Hidalgo del glabrous; n=^0 (Figs. 7, 8). Parral fowai'd El Vergel out of vSiui Fi'ancisco Locally common on high mountain del Oro, about 60 mi W Parral and 18.5 mi W Ojito. Sierra Madre Otridental. Durango, grassy plains, meadows, and in open f)ino- Mexico, at about 2450 m elevatioTu 11 Aug oak woodlands in the Sierra Madre Occi- 1971. Rereai Hess. & Kiger 27^7. Holotypus: dental of northern Durango and adjacent Its! Isotypi: ariz. asu, bry, ca,s, coi.o. gh, k, southern Chihuahua, Mexico, from 1550 to KANS, KSC, MEXU, MICH, MO, OKI,, OSC, P, RM, USA, SMU, TEX, VC. UTC, WTU 2350 m elevation. Flowering from .Tuh to October. Plants erect, 4-6 dm high; leaves linear, 0.3-0.7 Representative collections: MEXICO: Cliiliua (4) 6-12 (15) cm long, (0.2) hua: Norogadiic. 13-25 Nov 1885, Palmer J J (0.9) cm wide, sparsely strigose and September 197(i HESS. HKVEAL: REVISION OP ERKKJONUM 303

/•l^st^ation of Eriogonum atrorubcns var. nrmorosum showing » ^If .^ the general habit (A) and a detail of a single plant B) with close-up detail of the lower loaf surface, an involucre and flowers l,Vj;, and a mature achene (D). A

304 GREAT BASIN NATURALIST Vol. 36, No. 3

greenish above, densely grayish-tonientose wide, densely strigose on both surfaces; below; stems weakly fistulose in some; sterns not fistulose; involucres turbinate- mL'o/wcrt'.y turbinate-campanulate, (1) 1.5- campanulate, 1.5-2 mm long and wide, 2 (2.5) m long, 1-2 (2.5) mm wide, the the bractlets fringed with scattered hya- bractlets slightly hirsutulous and distinctly line hairs and shorter, capitate, gland- glandular; flowers glabrous; n = 20 (Figs. tipped hairs; floivers densely strigose with- 9, 10). out. Locally common in pine-oak woodlands Apparently local and infrequent, re- on the forest floor or on rocky limestone stricted to low, dry, rocky limestone out- outcrops, in the Sierra Madre Occidental crops in the desert ranges of east central in northern Durango and extreme south- Chihuahua, just northeast and east of Chi- ern Chihuahua, Mexico, from 2400 to huahua, Mexico, from about 1600 to 2000 2600 m elevation. Flowering from late m elevation. Flowering from June to July to October. September.

Representative collections: MEXICO: Chihua- Representative collections: MEXICO: Chihua- hua: 69 mi W Parral. 7 Oct 1969, Correll & hua:" Galdeano. E slope of Sierra de Santa

Gentry 22885 (encb) ; on road toward Campo Eulalia, 11 Sep 1934, Pennell 18673 (ny.

Alegre. 6.1 mi W Agua Caliente 15 Sep 1972. us) ; 4 km SE Rancho Encinillas, Sierra de Reveal & Hess 3121 (bry. mexu, ny. us. utc). Encinillas, near Fierro, 8-9 Jul 1941, Stewart Durango: 25.1 mi W Ojito, 15 Sep 1972, 760 (GH, TEX). Reveal & Hess 5105 (bry, ny. us, utc); 17.9 mi W Ojito, 16 Sep 1972, Reveal & Hess 3124 We have not seen the var. rupestre in (aRIZ, bry, CAS, GH, MEXU, MICH, NY, MO, OKL, the field, although we have explored in RSA, TEX, UC, US, UTC). the mountains around Chihuahua in The var. nemorosum differs from var. search of it. We both observed in our atrorubens in being a smaller plant with 1967 papers on this species complex that long, slender, linear leaves that are gray- Eriogonum rupestre ought to be considered tomentose on the lower surface, and in a a variant of E. atrorubens, echoing an number of features relating to the size and opinion expressed long before us by Johns- shape of the involucre, flowers, and fruits. ton (1944). Still, we have been reluctant It occurs in more shaded and mesic lo- to reduce the species until we saw the cations than does var. atrorubens^ and plants in the field. Now we are making generally (although not always) occurs at the reduction in spite of our lack of first- a higher altitude. It has not been found hand knowledge, feeling that the one with, or near, any known population of major discriminating feature—the pubes- var. atrorubens. The new variety is also cent flowers—is not enough to maintain similar to var. intonsurn, differing mainly this as a distinct species. in leaf shape and the overall size of the plants. Although the two occur in the same general region of Mexico, the var. inton- IB. Eriogonum subsect. Adenogonum sum is found at a lower elevation and on Eriogonum Michx. sect. Pterogonurn subsect. much drier sites. We have noted no over- Adenogorutni Hess & Reveal, subsect. nov. — lap in the range of the two varieties. subsect. Plerogorio pefiolis late laniinaiibus et inflorescontiis e non nisi aliquot lamis (Hffert. Typus: Eriogonum cilialum Toir. ex Benth. hi DC. If. Eriogonum atrorubens var. rupestre (S. Stokes) Hess & Reveal Plants of moderate height, 2-6 dm high; leaves oblanceolate^ to elliptic or spathu- Fig. 41. late, 1-5 cm long. 0.5-2.5 cm wide, usually Eriognnum atrorubens luigelm. in Wisliz. var. on broadh laminar petioles; sterns erect, rupestre (S. Stokes) Hess Reveal, stat. & & slender, glabrous or more frecjuently comb, nov., based on E. rupestre S. Stokes, glandular at least at the nodes; inflores- Gen. Eriog. 21, 1936.-—Rocky limestone slopes near Chihuahua. Chihuahua. Mexico, Aug cences o[ien, sparsely branched, glabrous 1885, Pringle 285. Holotype: uc! Isotypes: or glandular at the nodes; flowers white BM, BRY, DS, E, F, G, GH, ISC. K, MIN, MO. NY. to cream-colored, or if maroon, then witli P, PENN, PH, RSA, us, Vt! a bright yellowish center within, glabrous Plants erect, 4-9 dm high; leaves oblong or glandular. to oblanceolate, 4-10 cm long, 1-2.5 cm A subsection of lour species. SopteniluT 197() iii.ss. hi.vkal: iuaimon oi- kiuchkjnum 305

' r ^ \ : ^ m ^

H* ^^^.'^^"ii/i^-l'-

Fig. 41. Illustration of Eriogonum atrorubens var. rupestre showing the general habit (A.) and a detail (B) of a single plant, with an involuci'e and strigose flowers (C), and a mature achene (D). 306 GREAT BASIN NATURALIST Vol. 36, No. 3

Key to the Species of Subsect. Adenogonum

A. Flowers maroon; plants of the foothills along the western slope of the Sierra Madre Oriental and associated desert mountain ranges in Nuevo Leon, Coahuila, Tamaulipas, and San Luis Potosi, Mexico 2. E. cilintum

AA. Flowers white or cream-colored; plants of low desert ranges in gypsophilous area. B. Nodes and some branches glandular; tepals minutely glandular: inflorescences of 1-4 divisions. C. Leaves elliptic, 1-2 cm long, 0.8-1.2 cm wide, glabrous except for the ciliated margins; plants of Nuevo Leon 3. E. fimbriatum CC. Leaves narrowly oblanceolate to narrowly elliptic, L5-4 cm long, 0.5-0.9 cm wide, villous; plants of Zacatecas and San Luis Potosi 3. E. viscanum BB. Nodes and branches glabrous; tepals glabrous; inflorescences of 3-5 divisions; leaves broadly elliptic, (1) 1.5-2.5 (3) cm long, (0.5) 1-1.5 cm wide, glabrous below, villous above; plants of Zacatecas and San Luis Potosi E. rlirosum

2. Eriogonum ciliatum Torr. ex Benth. the succeeding peduncles (1) 2-7 cm long, in DC. glabrous except for the glandular base; Fig. 42. involucres campanulate, 3-5 mm long, 3-5 (7) mm wide, glabrous within and Eriogonum cilinlum Torr. ex Benth. in DC, Prodr. 5 shallow teeth 1-1.8 14: 20. 18o6.-—Camp at Buena Vista, south- without, the rounded, southwest of Saltillo, Coahuila, Mexico, 28 Jul (2) mm long, often ciliate, the bractlets 1848. Edwards s.n. Lectotype: ny! linear-oblanceolate, 1.5-3 (4) mm long, whitish Tall, erect herbaceous perennials 2-6 densely hirsutulous with long, cells, the pedicels 2-4 long, glab- dm high from a short, branched, woody (5) mm rous; flowers maroon with a darker red- caudex; leaves essentially basal, the leaf- dish midrib and often a bright, golden- blades spathulate, 1-5 cm long, 1-2.5 cm yellow within. 1.5-2.5 long in wide, glabrous on both surfaces except center mm anthesis, 3-4 long in fruit for the strigose midvein and margin, the becoming mm and somewhat greenish red at the base, apex obtuse with an apiculate tip, the glabrous, the tepals lanceo- base abruptly tapering to a broad laminar monomorphic, late to obovate, connate at the base; petiole, the petiole 0.5-4 (5) cm long, winged, ciliated, the petiole-base glabrous stamens slightly exserted. 1.5-2.5 mm long, the filaments glabrous, the anthers on both surfaces or merely strigose with- red; achenes greenish brown to light out; stems erect or nearly so, slender, not brown, 3-4.5 long, ovate, slightly fistulose, 2-4 dm long, glabrous except at mm ridged the entire length; — IO (Figs. the nodes where stipitate-glandular in n 11, 12). most; inflorescences usually open, cy- Locally on low hills and mose, mostly with one side suppressed, or common dry plains in T.arrra, pine-oak. or pinyon- dichotomously branched 1-3 times, oc- iunijier woodlands niainlv along the foot- casionally reduced to a single, terminal involucre, i-3 (4) dm long, the main branch hills of the Sierra Madre Oriental and associated desert ranges, from western bracted, the secondarv branch of the dichotomy an elongated peduncle, glabrous Nuevo Leon and southeastern Coahuila except for the stipitate-glandular nodes southward through central Tamaulipas to north (entral vSan Iaus Potosi, Mexico, and lower segments; bracts scalelike, ternate, 1-5 mm long, narrowh^ triangular from 1200 to 2300 m elevation (Map 2). P'lowering to to linear, usually glandular wathout. oc- from May September. casionally glabrous. s|)arsolv ciliated on ni.PHKSF.NTATiVF. .SPECIMENS: MEXICO: Conliuila: the margin, connate at the base; prdimclcs Near Buena Vista. 22 May 1847. Grvf-a 7VJ (mo); r.as Playas. 24 May 1071 Johnston et ascending or erect, straight or slightly al. tt210D fii., us); vSan T.oi-rnzo Canyon. S of curved, the first 5-20 peduncle (m long. Saltillo. 21 2^ Sep 1004. Palmer W5 (mo, S('[)tcilll)(>r 1<)76 HKSS, RKVKAL: lUlVISION OV KRKKiONl'M M)7

Fig. 42. Illustration of Eriogonum ciliatum showing the general habit (A) and a detail fB) of snigle a plant, with an involucre and flowers (C), and a mature achene (D). 308 GREAT BASIN NATURALIST Vo. 36, No. 3

NV, us); Carneros Pass, 4 Sep 1889, Pringle high from a small, compact, slightly 2379 (br, g. mo. ndg, ny, us); 0.3 p, mi E woody caudex; leaves basal, the leaf- Mex. Hwy 57 along rd to San Lirios, SE of blades elliptic, 1-2 cm long, 0.8-1.2 Saltillo, 5 Aug 1971, Reveal et al. 2612 (ariz, cm BRY, C.'XS, GH, MEXU, MICH. MO, NY, OKL, RSA, wide, glabrous and green on both surfaces,

TEX, uc, US, UTc) ; 0.5 mi S Estacion Caraeros, the margin ciliated with villous hairs, the 5 Aug 1971, Reveal et al. 2616 (bry, ny, us, apex mostly slightly acuminate, the base UTc). Nuevo Leon: Ascension, Jun 1930, Vie- abruptly tapering to a winged petiole, the reck 527 (us). San Luis Potosi: Charcas, Jul- Aug 1934, Lundell 5463 (ariz, us); 6 km E petiole (1) 1.5-2.5 cm long, glabrous, Laguna Seca, 10 Sep 1955, Rzedowski 6515 ciliated, the petiole-base glabrous except (mo, tex). Tamaulipas: 22 km SE Bustamante for the margin; stems erect, slender, not toward Tula, 20 May 1973, Johnston et al. fistulose, 0.5-1.5 dm long, glabrous 11148 (ll, us); near Miguihuana, 8 Aug 1941, (2) Stanford et al. 748 (ariz, mo, ny). throughout; inflorescences open, cymose, divided only once or twice with an ul- Unlike the other members of the sub- timate, non-dichotomous node above, (3) section Adenogonum that have whitish 5-8 (10) cm long, glabrous above, glandu- flowers, or cream-colored Eriogonum lar below at the node with small, nearly ciliatum has maroon flowers sirhilar to sessile, white, capitate glands; bracts those of E. atroruhens of Pterogonum and scalelike, 1-2.5 mm long, lanceolate, of E. hemipterum section Astra. However, glandular without, essentially glabrous upon a closer examination one quickly within, connate at the base; peduncles discovers the large, yellowish center of the slender, erect, straight or slightly curved, flower-tube a feature unique to E. cilia- — the first peduncle up to 6 cm long, the tum and not found in the other species succeeding peduncles up to 3 cm long, in the subgenus. In addition, characteris- both glabrous except for the stipitate- tics such as the laminar petioled leaves, glandular nodes and lower segments; the glandular nodes, and the highly re- ifivolucres campanulate, 2.5-3 mm long, duced inflorescences are not evident in 2.8-3.5 (4) mm wide, glabrous within subsection Pterogonum but are shared and without, except for the ciliate margins with the other members of Adenogonum. of the teeth, the 5 broadly acute lobes This species is easily recognized in the 0.7-1 mm long, the bractlets linear- field by the combination of ciliated, usual- oblanceolate, 2.5-3.5 mm long, densely vil- ly spathulate leaf-blades, maroon flowers, lous with long, non-glandular cells, the and reduced inflorescences. Rarely, ])edicels 1.5-2 mm long, glabrous; floivers whorled leaves may be found in the axils white to yellowish white with a broad of the temate bracts at the first node. brownish red midrib and greenish bro\Mi However, no confusion should occur be- base, (2) 2.5-2.8 mm long in anthesis, between Eriogonum ciliatum and the spe- coming 3-3.2 mm long in fruit, glabrous cies of Astra which have true cauline except for the minvite glands on the mid- leaves and no fused ternate bracts below rib and base, the tepals essentially mono- them. In addition, the known ranges of morphic, elliptical, those of the outer the species of Astra do not overlap the whorl slightly broader than those of the geographical range of E. ciliatum, and inner whorl; stamens included. 1.8-2.5 sim])]y by distribution the two can be mm long, the filaments glabrous, the separated. anthers yellowish; achenes light brown, 3-3.5 mm long, ovate, only the upper 1/3 of the fruit distinctly ridged; /2 = 20 (Fig. 3. Eriogonum fimbriaturn Hess & Reveal 13). Fig. 43. Locally connnoti on dry gypsophilous Eriogonum jimbrialiini Hess & Reveal, spec, hills and flats associatecl with Earrea nov. A E. ciliato floribus albis et a E. viscano south of San Rol)orto .lunction. Nuevo foliis latioribus, a E. clivoso caulibus glaiidulo- Leon, Mexico, from 1800 to 1850 m ele- sis differt. —Typus: Along Mexico Highway

57, 1 1 mi S San Roberto .lunction, Nuevo vation (Map 2). Probably flowering Leon, Mexico, on low limestone hills at ii!)()iit from August to October. 1800 m elevation, 19 Sep 1972, Reveal & Hess 3144. Holotypus: us! Isotypi: ariz, bry, cas, I^KlMtHSFNTATlVl. M'l'.CIMENS: MEXICO: NuBVO COLO, O, GH, K, MEXU, MICH, MO. NY, OKI., P, 1, (>(')[!: 11 mi S San Robeito .lunction. 5 Sep RSA, US, UTC, WTU! 1971, Bacon et al. 1113 (tkx); 14-15 mi S San Roberto Junction. 20 Aug 1973, Powell & Erect herbaceous perennials 2-3 dm Tonih 2564 (us). ScptCinlx'I- l*)7(l lll.ss. lU.VF.AL: RK\ISI0N Ol- I.UKH.ONUM 309

Fig. 43. Illustration of Eriogonum fimbrialum showing the general habit (A), and a detail fB) of a single plant, with an involucre and flowers (C). and a mature achene (D). A

310 GREAT BASIN NATURALIST Vol. 36. No. 3

Currently, Eriogonum fimbriatum is with a few scattered hairs, connate at the known from only one area south of San base; peduncles slender, erect, straight or Roberto Junction in Nuevo Leon. It is to slightly curved, the first peduncle up to be expected elsewhere in the area. We as- 6 cm long, the succeeding peduncles up to sume its distribution will be hke that of 3 cm long, glandular nearly throughout the related E. viscanum—very local, very their length with stipitate-glands; invo- isolated, and in widely scattered locations. lucres campanulate, 1.5-2 mm long, 2.5- Likewise, we can attest that it and most 3 (3.5) mm wide, glabrous within and likely E. viscanum are difficult to see in without, the 5 broadly acute teeth 0.5-0.7 the field, with their small stature, thin mm long, ciliate, the bractlets linear- stems, inconspicuous flowers, and strictly oblanceolate, 1 .5-2.5 mm long, densely vil- basal leaves. And when one considers the lous with long non-glandular cells, the feeding habits of goats, sheep, horses, bur- f)edi(els 1-1.5 mm long, glabrous; flowers ros, and cattle on these species in northern white to cream with a broad brownish Mexico, it is often a matter of luck that red midrib and base, 1.5-2.5 mm long in more than a single specimen can be found. anthesis, becoming 2.5-3 mm long in fruit,

Eriogonum fimbriatum is most closely glabrous or minutely glandular without, related to E. viscanum. The two differ glabrous within, the tepals essentially mainly in the shape and size of the basal nionomorphic, elliptical, those of the outer leaves, the leaf pubescence, and the ar- whorl slightly broader than those of the rangement of the glands along the stems. inner whorl; stamens included, 1.5-2.5 The former occurs to the east of the latter, mm long, the filaments glabrous, the an- but in essentially similar habitats. A com- thers red dish-yellow ; achenes (when still parison of the two descriptions will reveal immature) about 3 mm long, narrowly the other subtle differences as well, but ovate, only the upper Vs of the fruit dis- on the whole these are the major, macro- tinctly ridged. morphological differences. Rare and local, known only from scattered locations on dry gypsum hills and flats west of Concepcion del Oro, Zacate- 4. Eriogonum viscanum Hess & Reveal cas, and southwest of Cedral, San Luis Fig. 44. Potosi, Mexico, from 2000 to 2200 m ele- Eriogonum viscanum Hess & Reveal, spec. nov.— vation (Map 2). Probably flowering from ; E. fimbriato foliis longioribus, laminis villosis May to September. (non glabris), peduiiculis glandulosis et a E. clivoso caulibus glandulosis differt. Typus: — Represent.xtive SPECIMENS: MEXICO: San Luis Cedros, Jun-Aug 1908, Lloyd 116. Holotypus: Potosi: 17.5 km SW Cedral. 17 May 1973, mo! Isotypi: uc, us! Johnston et at. 11063.A (i.l). Zacatecas: 2 km Erect herbaceous perennials 2-3 dm SE Caopa. 17 .lun 1072. Chiang et al. 7 SSI A (i.i.~); on hills near Cedros. Aug 1908. Kirk- high from a small, compact, slightly wood 224 (f). woody caudex; leaves basal, the leaf- blades oblanceolate to narrowly elliptic, Eriogormm viscanum is clearly related 1.5-4 cm long, 0.4-0.9 cm wide, villous to E. fimbriatum. differing, as noted pre- on both surfaces or glabrous above ex- viously, mainly in leaf characters and pub- cept for the villous midvein, the margin escence features. At present, the species ciliated with sparse, villous hairs, the apex is known only from four collections, acute, the base tapering gradually to a three of whicli consist of an individual narrowly winged petiole, the petiol(» 0.5- |)lant. The Kirkwood collection comes 1 cm long, villous es})ecially along the from the same area as the tvpe and quite margin; stems erect, slender, not fistulose, possibly was collected at the same time 1-1.5 dm long, glabrous throughout; in- and place as the type. Lloyd and Kirk- florescences open, cymose, divided 2-4 wood were employed by the same com- times with an ultimate non-dichotomous |)an\ at the time of these collections. We node above, 5-15 cm long, glabrous on the liave attempted to locate this species in ui)f)er half of each branch, the lower half the fi(»ld without success. Reveal and N. and each node glandidar with small, caf)!- Duane Atwood, then at Rrigham Young tate, reddish glands; bracts scalelike, 1-3 Universitv, also searched in the Cedros mm long, narrowly lanceolate, glandular arvix. but not one plant was found in all without, essentially glabrous within or our joint or separate efforts. Although the Sef)tonil)('r 1*>7fi Iir.SS. HKVKAL: RF.VISION OJ' KRIOGONUM 311

Fig 44 Illustration of Eriogomim liscanum showing the general liabit (A) and a detail (B) of a single plant, with an mvolurre and flowers (C). and an immature acliene (D). A

312 GREAT BASIN NATURALIST Vol. 56, No. 3

description is based on this meager ma- length of the fruit; 72=20 (Figs. 14, 15). terial, we are still convinced that the spe- Local and infrequent to rare on dry cies is unique. limestone hills and flats east of Salinas del We have seen two collections which Penon Blanco along the Zacatecas-San might represent another new species in Luis Potosi state line, Mexico, from 1900 this group. It is from a gypsum outcrop to 2000 m elevation (Map 2). Flowering 1.5 miles southwest of Las Delicias in from July to October. Coahuila. Hopefully more material of this Representative specimens: MEXICO: San Luis entity will be collected and the nature of Potosi: Known only from the type collection. the plants determined. Zacatecas: 10 mi SE Salinas, 13 Jul 1966, Moran 13347 (so); 10 mi SE Salinas. 7 Aug 1971, Reveal et al. 2664 (ny. us). 5. Eriogonum clivosum Hess & Reveal Fig. 45. It is difficult to interpret the significance of the eglandular nature of Eriogo- Eriogonum clivosum Hess & Reveal, spec. nov. — E. fimbriato et E. viscano inflorescentis glabris num clivosum, with its more highly differt. —Typus: Along Mexico Highwaj' 49. branched inflorescence and the lack of a 53 mi E Zacatecas, 5 mi W El Tecomate and distinctly winged petiole so typical of the 4.5 mi E turnoff to Salinas del Penon Blanco, other species of the subsection Adenogo- on low limestone hills 1 km N of the highway, at 1900 m elevation, San Luis Potosi, Mexico. num. We have placed E. clivosum wdth 18 Sep 1972, Reveal & Hess 3143. Holotypus: E. viscanum and E. fimbriatum firstly us! IsOtypi: BRY, K, NY, UTC! on the basis of flower color—a charac- Erect herbaceous perennials 2.5-3 dm teristic we chose not to consider important in of E. high from a stout, compact, slightly the case ciliatum and the subsection Pterogonum. This inconsistency is woody caudex; leaves basal, the leaf- balanced by other characteristics such as blades broadly elliptic, (1) 1.5-2.5 (3) the leaf shape and pubescence of E. clivo- cm long, (0.5) 1-1.5 cm wide, glabrous below, sparsely pubescent above with long sum which are similar to that of E. cilia- and E. fimbriatum. inflores- villous hairs, the margin ciliated with tum The cence of E. clivosum is more branched dense villous hairs, the apex obtuse to mu- than any other of Adenogonum, cronate, the base abruptly tapering to a member but not nearly as much as that seen in non-winged petiole, the petiole 1-5 cm E. atrorubens of subsection Pterogonum. long, strigose, the petiole-base densely stri- And lastly, E. clivosum occurs in the low, gose without, sparsely so within; stems dry desert ranges, similar to those occu- erect, slender, not fistulose, 1-1.6 dm long, pied by E. viscanum and E. fimbriatum. glabrous; inflorescences open, cymose, di- and this ecological feature is not shared vided 3-6 times, 1-1.5 dm long, the by E. atrorubens except for var. rupestre. branches and nodes glabrous; bracts scale- On the whole we have felt it best to as- like, 1-4 mm long, triangular to lanceolate, sociate E. clivosum with glabrous without, sparsely pubescent with- Adenogonum rather than establishing a distinct sub- in, connate at the base; peduncles slender, section for it. erect, straight or slightly curved, 1-5 cm long, glabrous; involucres turbinate- campanulate, (2) 2.5-3 mm long and wide, II. Eriogonum sect. Peregrina glabrous within and without, the 5 acute Eriogonum Michx. subgen. Pterogonum (H. teeth 0.7-1 mm long, the bractlets linear- Gross) Reveal sect. Peregrina Hess & Reveal, oblanceolate, 2-2.5 mm long, densely sect, nov.- -A sect. Pterogono plantis glandulosis glandular, the pedicels 2-4 mm long, et caulibus foliatis differt. Typus: Eriogonum greggii Torr. Sz Gray. glabrous; flowers white to cream colored with a faint yellowish hue and with a Low, erec I ])erennial herbs with few to wide reddish brown midrib and base, (1.5) several stems arising from branched 2-2.5 mm long in anthesis, becoming 2.5-3 caudices, glandular throughout; leaves mm long in fruit, glabrous, the tepals basal and cauline in the axils of bracts, monomor[)hic, lanceolate to oblong; sta- spatludate, hispid and stijiitate-giandular mens slightly exserted, 2-2.5 mm long, the or rarely glabrous on both siu'faces; filaments glabrous, the anthers pink to bracts ternate, scalelike to semifoliaceous, light red; acfienes light brown, 3 nun connate at the base; peduncles long and long, ovate, ridged nearly the entire usually stout; irwolucres canif)anulate, the 1976 September iiess, rkveal: hk\ision of erioglOGONUM 313

^ H^

Fig. 45. Illustration of Eriogonum cliiosum showing the general habit (A) and a detail CB) of a single plant, with an involucre and flowers (C). and a mature achene (D). 514 GREAT BASIN NATURALIST Vol. 36. No. 3

5 teeth mostly acute, the bractlets linear- leaves basal and cauline in axils of ternate oblanceolate, hirsutulous, the pedicels bracts, the basal leaf-blades broadly spath- glandular and hispid; flowers yellowish ulate, 2-6 (10) cm long, 0.5-2 (2.5) cm white often with a broad reddish brown wide, glabrous except for the ciliated mar- to brown midrib, the tepals strigose; gins and midvein, or hispid and uniformly anthers green or red; achenes ridged stipitate-glandular on both surfaces, the nearly the entire length of the fruit, apex obtuse or infrequently acute, often glabrous. with an apiculate tip, the base long cune- The section Peregrina is composed of ate and tapering to a ±winged petiole, but one species, Eriogonum greggii. It dif- the petioles 0.5-2 cm long, hispid and fers from all other species in the subgenus glandular, the cauline leaf-blades oblan- in being densely glandular and hispid, ceolate, obovate, or spathulate, in a whorl having a suppressed inflorescence, strigose of 3-7 at each node, 0.5-4 cm long. 0.2-1.5 tepals, and a haploid chromosome number (2) cm wide, similar to the basal leaves of n = \Q. The single species ranges from only more hispid or glabrous except for extreme southern Texas southward into the margins and midveins, the apex acute northeastern Mexico, occurring mainly in to mostly obtuse, the base cuneate, sessile; the limestone ranges and mountains as- stems erect or nearly so, slender, 5-15 cm sociated with the Sierra Madre Oriental. long, glandular; inflorescences c}Tnose We have placed Eriogonum greggii in with one side suppressed, branching 3-15 subgenus Pterogonum following Stokes times, 1-3 dm long, the main branch (1936) rather than Watson (1877), who bracted and divided with the lateral associated the species with the subgenus branches highly reduced or mostly lacking, Ganysma. As discussed previously, we the secondary branch of the dichotomy have concluded that this is the only rea- actually an elongated peduncle, glandular sonable treatment, but our efforts to satis- throughout; bracts scalelike to semifolia- factorily place E. greggii in Pterogonum ceous, ternate, 3-15 (22) mm long, lanceo- have been difficult. It seemed to us that late, glandular and hispid with ciliated we could not associate it with E. atro- margins, or merely glabrous and ciliated, ruhens, and certainly not with E. alatum connate at the base; peduncles ascending or E. hieracifolium. On the basis of the to erect, straight or slightlv curved, 1-6 broadly laminar petioles, spathulate leaves, (7) cm long, glandular and hispid; invo- and modified inflorescences, it did not lucres campanulate, 1.5-3 mm long, 3-5 seem to be that closely related to E. cilia- mm wide, slightly to densely strigose and tum. However, the features of pale yellow- glandular without, glabrous within except ish white flowers wath the broad reddish for the ciliated margins, the 5 acute teeth midvein and glandular pubescence make 1-1.5 mm long, the bractlets linear- it possible to relate it to other members in oblanceolate, 1.5-2 (2.5) mm long, slight- subsection Adenogonum. But because the lv hirsutulous with glandular and non- plants of E.. greggii are wholly glandular glandular hairs, the pedicels 2-3 (4) mm and hispid, the tepals strongly strigose, long, glandular and hispid; flowers yel- and the leaves both cauline and basal, we louish white with a broad and predomi- could only propose a distinct section for it nant dark reddish brown to brown midrib while acknowledging that it is more close- and base, 1.5-2.5 nun long in anthesis. be- ly related to Pterogonum than either coming mon^ reddish and 2.5-3.5 nun long Astra or Alata. in fruit, strigose without, glabrous within, the tepals monomorphic. lanceolate to ob- 6. Eriogonum greggii Torr. & Grav long; stamens slightly exserted. 1.5-2 nmi anthers Fig. 46. long, the filaments glabrous, the green or red; acJienes reddish brown, 3-4 F.riniionurn greggii Torr. & Gray, Proc. Amer. nun long, ovate, slightly ridged the entire Acarl. Arts 8: 187. 1870, haspfl on E. ciliatum length of th<^ fruit; /?=16 (Figs. 16. 17, Torr. I'x Bcritli. in DC. v;ii- foUosuni Ton-, in Emory. Rep. U.S. & Mox. Boundary Sui-v. 171 and 18). 1869. —High plains at San Juan de la Vcguoria, Locally common in open grasslands, Coahuila, Mexico, 20 May 1847, Grrpa s.n. dry arid slopes, or pine-oak woodlands Holotypc: ny! Isotypes: gh, mo! on the plains and lower foothills of the Low, erect herbaceous perennials 1-4 desert mountain ranges and Sierra Madre dm high from a short, woody caudex; Oriental, from extreme east central and September 1976 hess. re:veal: rf.vision of kriogonum 315

Fig. 46. Illustration of Eriogonum greggii showing the general habit (A) and a detail TB) of a single plant, with an involucre and flowers fC). and a mature achene (D). H-

316 GREAT BASIN NATURALIST Vol. 36, No. 3 southeastern Coahuila and adjacent west uate cymes; peduncles usually stout; in- central Nuevo Leon, Mexico, northward volucres turbinate to camj)anulate, the 5 to Hidalgo Co., Texas, from 100 to 2300 teeth mostly acute to truncate, the bract- m elevation (Map 2). Flowering from lets linear-oblanceolate, glabrous or gland- March to October. ular, sometimes ciliate, the pedicels glabrous or pilose at the base; flowers ma- Represent.ative COLLECTIONS: MEXICO: Coa- to huila: Santa Catarina, 26 Apr 1939, Frye & roon yellow or cream colored, the tepals

Frye 2512 (ds, mo, ny, uc, us. utc) ; 1 mi glabrous to strigose; anthers maroon to N Rancho de la Gavia, N side Sierra de la yellow; achenes winged on the upper Gavia, 18 Mar 1973, Johnston el al. 10277 third, pilose at the apex. (ll, us); Saltillo, May 1898. Palmer 166 (mo, NY, s, uc, us); 3.6 mi S Santa Teresa, The species of sections Astra and Alata Sierra de la Muralla, 4 Aug 1971. Reveal et al. have leaves that are alternate on the stems, 2607 (bry, mexu, ny, us, utc). Nuevo Leon: a characteristic not shared by any of the N Dr. Arroyo, 5 Sep 1971. Bacon et al. 1131 species in sections Pere- (tex); 9 km W Villa Garcia toward Icamole. Pterogonum and grina. The only glandularness present in 4 Jul 1973, Johnston et al. 11601B (ll, us); 1 mi E Cuesta de Aves, between Saltillo and Astra is that associated with the minute Monterrey, 22 Sep 1973, Reveal & Atwood bractlets found within the involucre. The 3382 (ariz, bry, c^s, gh, mexu, mo, ny, okl. cymose paniculate inflorescence is quite RSA, TEX, uc, us, UTc) . distinct, giving the plants of Astra a to- In all its localized phases, Eriogonum tally different appearance from those spe- greggii may be quickly recognized by its cies previously discussed. general habit and vestiture. It is rather The multiple branched caudices, many variable, however, in the amount and of them with flowering stems, distinguish distribution of both glands and hairs, as Astra from the monocarpic condition of some individual plants may have glabrous section Alata. In addition, most of the spe- leaf-blades (except for the margins and cies of Astra have fruits that are pilose midvein), or merely hispid leaves, or only and winged on the upper third as opposed glandular leaves. In less frequent cases, to the plants of Alata which have glabrous the stems show a similar degree of vari- fruits that are winged the entire length. ability, but the vestiture of the leaves and The distribution of the members of Astra stems is not always correlated. No geo- is primarily in the mountains and arid graphic or edaphic restrictiveness is evi- regions of the southwestern United States dent concerning this feature and inter- and occasional places in the moinitains and mediates occur commonly. Some plants foothills of extreme northern Coahuila and may be less erect than others in the same northeastern Chihuahua in Mexico. Only population, while there is a great range Eriogonunt hemiptrrum var. griseuni has in flowering times from individual to in- its distribution solely in Mexico, and then dividual. While this variation may be seen it is restricted to the mountains essentially in the field, the species is easy to distin- just south of the Chisos Mountains of guish throughout its growth cycle and can- Texas. The other taxa, with the exception not be confused with other species of the of E. hieracifolium, are found locally in genus. Texas or just over the boiuidary into northern (>oahuila, Mexico. The exception III. Eriogonum sect. Astra is also locally common, but with a wider Eriogonum Michx. subgen. Pterogonum (H. distribution, ranging in a narrow band Gross) Reveal sect. Astra Hess & Reveal, sect. across western Texas through New Mexico nov. —A sect. Pterogono prcsentia foliis caulibus into eastern Arizona northern Mexico. atque inflorescentiis paniculatis differt et a and sect. Alato herl)a pereimia a raniosus caudice; Th(> maroon flowers of Eriogonum achaenia alata superioribus tiMtioribus. pilosa. /leniipterurn easily distinguish it from the Typus: Eriogonum hieracifolium Beiith. in DC. remaining members in section Astra. As Tall, erect perennial herbs mostly with will be discussed later, it was originally a single stem arising from a branched ( oii'^idered as a red-flowered \ariety of caudex; leaves basal and alternate, the the yellow-flowered E. hieracifolium. We leaf-blades spathulate to oblanceolate, stri- have on hand

Sej)tenil)or 1976 IIKSS. Hl.VEAL: HKMSION OF KUKKJONl'M 317 fruit. The significance of this transitional cymose inflorescence, plus the pubescent characteristic is not clear with respect to stems, reflect a more exact association of E. fu-miptcruni and K. hicrdcifnliuni and, these species than flower color. Likewise, as yet, neither of ns has been able to ob- the distribution of the species of Astra, as tain more plants or investigate this [)he- opposed to that of Pterogonum, strength- nomenon in the field. ens our i)osition as well. The section is We feel strongly that the presence of well defined, easily recognized, and com- stem leaves and an elongated f)aniculated posed of onh' three species.

Key to the Species of Sect. Astra

A. Inflorescences strigose to thinly or densely tnriientose; flowers yellow to maroon, strigose. B. Flowers yellow-, sometimes maturing with a reddish tinge; basal leaves usually densely strigose; east central Arizona across central and southern New Mexico to western Texas, and southward to northern Coahuila and Chihuahua, Mexico 7. E. hieracifoUum BB. Flowers maroon; leaves thinly strigose and green on both surfaces, or densely tomentose below and green above; plants of moderate to high elevation in the mountains of Brewster Co., Texas, south to northern Coahuila and northeastern Chihuahua, Mexico

._. 8. E. hemipterum

AA. Inflorescences glabrous; flowers cream colored, glabrous to thinly strigose; grassy hills and plains of west central Texas 9. E. nealleyi

7. Eriogonurn hieracifoUum Benth. in DC the base cuneate to the stem; stems erect Fig, 47. or nearly so, slender, 3.5-5.5 dm long, densely strigose; inflorescences open panic- Eriogonurn hieracifoUum Benth. in DC. Prodr. 14: 6. 1856—Guadalupe Mountains of northwestern ulate cymes, the branches restricted to the Culherson Co., Texas, or perhaps in south- uppermost part of the plant, 4-15 (18) western Eddv Co., 15-16 Oct New Mexico, cm long, strigose throughout; bracts scale- 1849. Wright 616 (his 1323). Holotype: gh! like, ternate 2-8 long, linear-trian- Isotypes: gh, k, ny. uc, us! —Pterogonum mm hirracifoliurn (Bentli. in DC.) H. Gross. Hot. gular to linear-lanceolate, the low^ermost Jahrb. Syst. 49: 239. 1913. infrequently lanceolate and up to 15 mm Eriogonurn panosum Woot. & Standi., Contr. U.S. long, strigose on both surfaces and espec- Natl. Herb. 16: 118. 1913. -Organ Mountains. ially along the margin, connate at the Dona Ana Co., New Mexico. Aug 1881. base; peduncles erect to ascending, straight Vasey s.n. Holotype: us! Isot^T^es: gh, isc, k, p, us! Eriogonurn leucophyllum Woot. & or curved, 0.5-3 cm long, strigose; involu- Standi, ssp. panosum (Woot. &: Standi.) S. cres turbinate-campanulate to campanu- Stokes, Gen. Eriog. 97. 1936. la te, 2.5-4 mm long, 2.5-5 mm wide, hir- Erect herbaceous perennials 4-7 dm sute to strigose without, glabrous within, high from spreading, branched, woody the 5 triangular teeth 0.5-1.5 mm long, caudices; leaves basal and cauline, the the bractlets linear-lanceolate, 2-3 mm basal leaf-blades oblanceolate to spathu- long, glabrous or minutely glandular, the late, (3) 5-15 cm long, 0.5-2 cm wide, pedicels 2-5 mm long, glabrous; flowers sparsely to densely woolly on both sur- yellow with greenish yellow midribs and faces, especially so below, the margin bases, 1.5-2.5 mm long in anthesis, be- ciliated with longer strigose hairs, the coming 3-5 mm long and reddish in fruit, apex obtuse or occasionally acute, the base white-strigose along the midribs and bases long cuneate to a narrowly winged petiole. without, glabrous within except for a few the petiole 0.5-5 cm long, strigose, the scattered hairs within at the base, the petiole-base strigose to woolly especially tepals essentially monomorphic. narrowly abaxially, the cauline leaf-blades oblan- ovate, connate at the base; stcmiens slight- ceolate. 0.5-5 cm long, 0.3-1 cm wide, ly exserted, 2-3 mm long, infrequently densely strigose below, less so above, the reduced and sterile, the filaments pilose margin ciliated, the apex mostly acute. basally, the anthers yellow, 0.5-0.6 mm 318 GREAT BASIN NATITRALIST Vol. 36, No. 3

Fig. 47. Illiistiiition of Frioiionuni /licrficifollurn sliciuiri^; tlic ^mmhmmI Ii.i1)iI (A) .iiiil a ilctiiil (B) of a single phiiit. with iin involiu ic and flowers ((]). and a maliirc ,i( liciie (I)). M

September \976 HKSS. HKVKAL: KIAISION OP FCRIOfJON I' 319 long; achcjics yellowish green maturing to tive about his itinerary and even if she a light brown, 4.5-6 mm long, 2.5-3.5 mm were correct, it is still unlikely that E. wide, j)andurate, tlie upper half winged, hieracifolium was collected there, partic- strigose, exserted; /7 = 20 (Figs. 19, 20). ularly since we have seen no collections Common in dry open places, mainly in of this taxon from Otero County. Mc- grasslands, j)inyon-juniper. and pine wood- Kelvey stated that Wright crossed the lands from northern Coahuila and Chi- Guadalupe Mountains in Culberson huahua, Mexico, north through western County, Texas, and this would seem to be Texas into southern and central New- the most likely area for his collection. Mexico, and just entering east central Another possibility is that Wright could Arizona, from 9()() to 2600 m elevation have wandered into Eddy County, New (Map 3). Flowering from July to Oc- Mexico, and made his collection there. tober. However, there is no indication that Wright and the small party of United Represent.\tive collections: 'MEXICO: Chihua- traveled a route (Geiser hua: Sierra de los Pinos. Dec 1937, LeSueur States troops such /533 (tex); above Santo Tomas between Cui- 1948), and because Wright was on foot, he dad Guerrero and Madero, 16 Aug 1959. likely remained close to the route taken Kruckeberg 4918 (ds, ny, us). Coahuila: 43 by the troops. Consequently, it is most km from La Linda, 8.5 km S Cuatro Palmas collection of E. hier- on the road to Mina Aguachile. 30 Jul 1973. likely that the type Johnston et al. 11959 (ll. us); 20 mi SE La acifolium was made in the Guadalupe Linda. 1 mi SE Cerro Aguachile. 30 Jul 1973. Mountains of Texas and not in New Hendrickson 11590 (us). UNITED STATES: Mexico. ARIZONA: Apache Co.: 1 mi from junction of Big and Little Diamond creeks. Jul 1964. The Vasey collection used by Wooton Applequist 101 (mn.^). Gila Co.: 1 mi N Black and Standley (1913) in erecting Eriogo- River. White Mts.. 22 Jun 1930. Goodman & num panosum was obtained a short dis- Hitchcock 1288 (bkl. ds. gh, mo. ny, okl. tance to the northwest of the Guadalupe uc); 10 mi N Salt River, 26 Jun 19-44. Pultz 1006 (ksc, mo, ny, uc). Navajo Co.: Ft. Mountains in the Organ Mountains of Apache. 26 Jul 1910, Goodding 683 (gh, ny. New Mexico. These two authors suggested us). NEW MEXICO: Bernalillo Co.: Near that their new species differed from E. Tijeras. 9 Oct 1939. Barneby 2415 (ny). hieracifolium in its kind of pubescence Catron Co.: 9 mi N Aragon, 9 Jul 1965, Weber & Salamun 12791 (colo. d.\o. ill, and smaller size of the leaves, involucres, okl). Dona Ana Co.: Van Paltens, Organ Mts.. and perianth parts. However, the variation 25 Jun 1894. Wooton s.n. fus). Eddy Co.: Hero among the plants, as examined by us both Ranch, near Queen. 4 Aug 1909. Wooton s.n. in the field and in the herbarium, has fus). Grant Co.: GOS Ranch, 27 Aug-12 Sep 1911. Holzinger s.n. (us). Lincoln Co.: Gray, indicated that recognition of E. pano- 17 Aug 1898. Skehan 96 (gh, k, ny, pom, uc, sum at any taxonomic rank is wholly un- us). Sierra Co.: 3.5 mi W Hwy. 52. N of warranted. The curious aspect of this spe- Winston, 25 Jul 1965. Hess 310 (okl, tex. cies is its treatment by Stokes (1936). uc). TEXAS: Brewster Co.: 29.5 mi W Sander- She included E. panosum as a subspecies son, 1 Aug 1971. Reveal et al. 2552 (bry. ny. us. UTc). Culberson Co.: 9.5 mi NE Pine of E. leucophyllum Woot. & Standi., and Springs, 4 Sep 1967, Reveal & Davidse 914 ". noted that it . . is on the borderline be- C.'XS, ds, ids. ISC. LL. MO. NY. RM. (aRIZ, bry, gh. tween the lachnogynum group and the Rs.\. SMU. TEX. UC US. UTc) ; 10 mi W Kent. 7 I and geographi- Aug 1949, Warnock & Turner 8944 (ll. s.mu). alatum group of Section Jeff Davis Co.: 2.5 mi S Kent, 3 Sep 1967. cally it is related to both." This incompre- Reveal & Davidse 913 (.ariz, bry, cas, colo. hensible arrangement and highly question- ds, gh, ids, ISC. KSC, LL, MO, NY, RM, CS, DAO. able statement of justification is simply rsa, SMU, TEX. UC. US. UTc) . Pecos Co.: 25 mi S foundation. Reveal (1969b) has Ft. Stockton. 5 Nov 1964. Correll & Correll without 30469 (ll). placed E. leucophyllum in synonymy under E. haimrdii S. Wats., and he has The precise locality of Wright's collec- I)laced the section Lachnog^na Torr. & tion of Eriogonum hieracifolium is un- subgenus Eucycla. We can- known. McKelvey (1955) discusses his Gray in the not explain the reasoning behind the itinerary as prepared by Ivan M. Johnston, Stokes arrangement. and from this, it appears that he was in Eriogo- Otero County, New Mexico, at the time of The phylogenetic relatiorrship of to the other species its collection. However, she w^as not posi- num hieracifolium

listing of locations. The distribution maps nn this specie and in Eriogonum alatum we are providing only a partial should supply the necessarj- detailed information regarding exact locations. 320 GREAT BASIN NATURALIST Vol. 36. No. 3 within Astra is probably greater with E. 2-4 mm long, (1.5) 2.5-4 mm wide, thinly hemipterum than with E. nealleyi. The to densely strigose without, glabrous with- differences are discussed under each of in, the 5 shallow, triangular teeth 0.5-1 the last two species respectively; however, mni long, the bractlets linear to linear- all share the paiidurate sha})ed, and often oblanceolate, 2-3 mm long, glabrous or pilose, achenes and the open, paniculate glandular and minutely ciliated, the pedi- cymose inflorescence. In the subgenus cels 2.5-6 mm long, glabrous; flowers ma- Pterogonnm, E. hieracifolium is unique roon, 1.5-2.5 mm long in anthesis, be- with bright yellow flowers. It has a strange coming 2.5-3.5 mm long and slightly less distribution pattern in that it is found reddish in fruit, rarely becoming yellowish mainly in the grasslands of the low desert red, strigose without especially along the ranges of northern Mexico, western Texas, midrib and base, glabrous within except and southern New Mexico, but occasional- for a few scattered hairs at the base, the ly it is found in pine woodlands in central tepals essentially monomorphic, narrowly New Mexico and Arizona, and in Chihua- spathulate to obovate, connate at the base; hua, Mexico. In this latter respect it is stamens slightly exserted, 2-3 mm long, somewhat like E. alatum, which occurs the filaments pilose basally, the anthers in similar habitats over a much larger reddish purple to maroon, 0.5-0.6 mm area of the western United States. Even so, long; achenes greenish, maturing reddish E. hieracifolium is essentially uniform brown, 3.5-5 mm long, 2-3.5 mm wide, throughout its range and is normally not pandurate, the upper third winged, stri- readily confused with other species of gose, exserted. Pterogonum. Locally common in the Chisos Moun- tains of Brewster Co., Texas, and in and 8. Eriogonum hemiptermn (Torr. & Gray) near the Sierra del Carmen, Sierra del S. Stokes Jardin, and the Sierra del Pinos of Coa- Fig. 48. huila, and in the Sierra Diablo of northeastern Mexico, 1200 to Tall, erect herbaceous perennials 2-8 dm Chihuahua, from high from spreading, branched, woody 2400 m elevation (Map 3). Flowering caudices; leaves basal and cauline, the from June to November. basal leaf-blades oblanceolate to elliptic or The two varieties of Eriof^onum hemip- spathluate, (2) 4-8 cm long, 0.5-1.5 cm terum. var. hemipterum and var. ^riseum. wide, thinly strigose and green on both have a distinct and limited distribution in surfaces or rather densely tomentose and the disjunct mountains of southwestern gray below, the margin sparsely ciliated Texas, northern Coahuila, and adjacent with short strigose hairs, the apex mostly Chihuahua, Mexico. There is no record acute, the base long cuneate to a narrowly of both varieties occurring in the same winged petiole, the j)etiole 0.5-3 cm long, moiuitain range. This should not be too strigose, the j)etiole-base s[)arsely strigose surprising, since in this area of the Chi- without, glabrous within, the cauline leaf- huahuan Desert, the mountain ranges are blades spathulate to oblanceolate, 1.5-5 cm generally sei)arated by dry desert valley long, 0.2-1 cm wide, thinly strigose on both floors. These effective barriers allow the surfaces or tomentose below, the margin small populations to evolve along their ciliated with long, strigose hairs, the apex separate wars, probably accovmting for acute, the base cuneate to the stem; anv of the minor xariation exhibited by stems erect or nearly so, slender, 1-6 dm them. long, thinly to densely strigose; inflores- The (lose relationship of F.rio

Illiistration of Eriogonurn e,Zl 1^ hemiptcrum. sliouing tlie general habit (A), detail of a involucre ^" with flowers (C). and a mature achene (D) of var. hemipterum. and aTSfll^Tleat-blade ofV'var. griseum (E) showing the more densely pubescent lower surface 322 GREAT BASIN NATURALIST Vol. 36, No. 3 two species. Their distributions are not elevations of these mountain ranges, quite as distinct as we once thought (Hess whereas E. hieracifoUum is restricted to 1967, Reveal 1969b) with the discovery the foothills and broad valley floors be- of E. hieracifoUum and E. hemiptcrum es- tween the desert mountains. sentially in the same mountain range in Eriogonum hcmipterum is composed of northern Coahuila. Nonetheless, E. hemip- two distinct variants which may be dis- terum is restricted to the middle and upper tinguished by the following key.

Key to the Varieties of E. hemipterum

A. Leaves strigose on both surfaces; involucres slightly strigose; bractlets glabrous; peduncles 0.5-8 cm long; plants of Chisos Mts., Texas, and the

Sierra del Carmen and Sierra del Jardin, Coahuila, Mexico .. 8a. var. hemiptcrum AA. Leaves strigose above and tomentose below; involucres densely strigose; bractlets pubescent; peduncles 1-12 cm long; plants of Sierra del Pinos and Sierra del Diablo, Mexico 8b. var. griseum

8a. Eriogonum hemipterum var. When Torrey first saw the type of this hemipterum species, he placed the Parry collection in

Figs. 48a. b. c, d. Eriogonum hieracifoUum (Torrey 1859). At a later date, apparently, he ascribed, Eriogonum hemipterum (Torr. & Gi-ay) S. Stokes, Gen. Eriog. 21. 1936, based on E. hieracifoUum without publishing, the herbariimi name Benth. in DC. var. hemipterum Torr. & Gray, of "E. hemipterum" to the collection, and Proc. Amer. Acad. Arts 8: 154. 1870.—Hill- when Torrey and Gra}^ (1870) proposed sides at Boquillas del Carmen along the Sierra the name E. hieracifoUum var. hemip- del Carmen, Coahuila, Me.xico. 8 Nov 1852, terum, this herbarium was cited in Parry s.n. Holotype: ny! Isotypes: isc, k! name synonymy. Stokes believing the Eriogonum hieracifoUum Benth. in DC. f. atropur- (1936), pureum Standi., Field Mus. Nat. Hist., Bot. entity to be specifically distinct, used the Ser. 11: 149. 1936. —Chisos Mountains, Brews- author citation of "Torr. in T. & G." in ter Co., Texas, 5 Aug 1931. MuUer 7977. her monograph, not realizing that the spe- Holotype: f! Isotypes: bkl, gh, ny, ttc, uc, us! cific combination had never been made. Johnston (1944), in attempting to correct Plants 2-7 dm high; leaves with basal her error, proposed the author citation as and cauline blades strigose on both sur- "Torr. ex Stokes." Goodman (1945) dis- faces; peduncles 0.5-8 cm long; involucres agreed, explaining that he believed Stokes slightly strigose without, the bractlets 2 intended to raise var. hemipterum to the mm long, glabrous; flowers 1.5-3 long; mm species level, and the citation of author- n=2{) (Figs. 22, 23). ship should read "(Torr. & Gray) S. Locally common in the canyons and Stokes." We concur with Goodman's in- mountainsides in the Chisos Mountains of terjiretation. southern Brewster Co., Texas, south to Until recently (Reveal 1968b, 1970), the Sierra del Carmen and Sierra del Jar- the name Eriogonum hemipterum has been din, Coahuila, Mexico, from 1200 to largely obscured by Standley's (1936) 2300 m elevation. Flowering from .Tune name, E. hieracifoUum f. atropurpureum. to November. Although Johnston (1944") was the first Representative collections: MEXICO: Coa- to [)lace the Standlcv name in .synon^Tmy huila: Sierra del Carmen, 14 Aug 1936, under A', hemipterum, this change went Marsh 660 (gh, te.\); N side of Pico de Cen lUHioticed collectors ob- tinela. Sierra del Jardin, 27 Jul 1973. Johnston mosth by who ct al. 11809 (ll, us). HNITED STATES: tained the species in Texas. A factor which TEXAS: Brewster Co.: Chisos Mts.: Oak probably prompted Standley to consider Creek, near the Window. 23 Aug 1936. the red-flowered Muller collection (no. Hinckley S35 (gh, ll, ny) ; Laguna, 28 Jul 7977) as a forma of E. hieracifoUum was 1932, Muller 16555 (mo. smu, t.aes, tex, us); along the Laguna Meadow trail to South Rim, another collection (Muller 797S) from the 3 Sep 1967, Kei.cal & Davidsc 906 (.\niz, nnY. same locality which fits the description CAS, COLO, CS, GH, ISC, KSC, LL, MO, NY, RM, RSA, of typical E. hieracifoUum. ('arefid field-

SMU, TEX, uc, US. utc) ; Oak and Willow cieeks work h\ both of us (plus numerous col- canyons, 26 Sep 1936, Sperry 216 (neb, taes, us). lectors before and after) has resulted m September 1976 HESS. HF.VEAL: REVISION OF ERIOGONUM 323 no collections of K. hicrdcifoliitm from the Representativf. SPECIMENS: MEXICO: Chihua- Chisos Mountains and until recently no hua: NW end of Sierra del Diablo, 29-30 Jul 1941. Sleuart 968 (gh. te.x). Coahuila; Sierra collections of E. hieracifolium within 100 del Pinos. Dec 1937. LeSueur /533 (gh) ; kilometers of the Chisos Mountains. We 25 km N La Noria, Sierra del Pinos, 29 Jul are at a loss to explain MuUcr 7978, but 1941. Stewart 1249 (gh). with the location of K. hieracifolium just We have not seen var. griseurn in the across the Rio Grande in the northern field, but we interpret what we know mountains of Coahuihu Mexico, a greater about its habitats from the scant informa- possibihty exists that it. perha])s. did oc- tion provided by Johnston (1944) and cur in the Chisos Mountains. Nevertheless, herbarium labels. The plants seem to oc- we do not believe that these two species cur on disturbed sites in open pine wood- are related at the infraspecific level. lands or grassy meadows. It is incon- The var. Jwmipteriim occurs in the gruous to us that we only know this va- moist canyons and wooded slopes through- riety from the same material Johnston out its range. In the Sierras del .Tardin based his description on over 30 years and Carmen, the f)lants may be occasion- ago. We are unaware of any recent col- ally found in more open, xeric sites, but lections which would supply us with ad- always at the higher elevations. In the ditional habitat data. Chisos Mountains, where we have seen several populations, the plants often occur This plant is generally taller and more var. in or under shrubs, with the inflorescence robust than hemipterum, and has running through the branches of the densely strigose involucres and leaves that shrubs. We have seen some plants occur- are tomentose on the lower surface. ring with various bunch grasses, and again, the inflorescences can be seen 0. Eriogonum nealleyi Coult. among the grass stems, but the basal Fig. 49. leaves and spreading caudices are hidden Eriogonum nralleri Coult.. Contr. LT.S. Natl. Herb. among the bunches of grass. As w^e shall 1: 48. 1890.—Near Pecos Cit^'. Pecos Co.. note below, we understand that var. gris- Texas. 1889. Nealley 455. Holotype: us! Iso- eum occurs in open forests quite divorced tvpes: gh. k! from other plants, and thus it is found as Tall, erect herbaceous perennials 5-12 scattered individuals on the forest floor dm high from spreading, branched, woody rather than closely associated with other caudices; leaves basal and cauline. the f)lants of its kind. basal leaf-blades oblanceolate to spathulate, 4-8 cm long. 0.5-1.6 cm wide, rather 8b. Eriogonum hcmipterum var. griseurn evenly strigose and grayish on both sur- I. M. Johnst. faces, the margin ciliated with long, stri- Fig. 48e. gose hairs, the apex acute or obtuse, the

Eriogonum hemipterum (Torr. & Gray) S. Stokes base long cuneate to a narrowly winged var. griseurn I. M. Johnst.. J. Arnold Arbor. petiole, the petiole 1-2.5 cm long, strigose, 25: 138. 1944.—Central part of the Sierra del the petiole-base strigose to glabrous with- Pinos. about 10 km N La Noria on a dr\\ out, glabrous wathin, the cauline leaf- western ridge near the head of an old log slide north of great cliffs. Coahuila, Me.xico, 22 Aug blades few, (0.5) 1-4 cm long, (2) 3-8 1940, Johnston & Muller 547. Holoty-pe: gh! mm wide, sparsely strigose, the apex acute, Isotype: TEx! the base tapering to the petiole-base; Plants 5-10 dm high; leaves with basal stems erect, slender. 2-4.5 (5) dm long, and cauline blades strigose above and to- glabrous; inflorescences open paniculate mentose below; peduncles 1-12 cm long; c\Tnes. the branches restricted to the up- involucres densely strigose without, the per half of the plant. 2-5 (7) dm long; bractlets 2-3 mm long, ciliate, glandular; bracts scalelike, ternate, 0.5-2.5 mm long, flowers (2) 2.5-3.5 mm long. linear-triangular to triangular, glabrous, Apparently local and scattered in open connate at the base; peduncles erect, places in pine woodlands of the Sierra del straierht or slightly curved, 1-8 cm long, Pinos, northeast Coahuila, and in Sierra srlabrous; involucres turbinate-campanu- del Diablo, northeastern Chihuahua, late to campanulate. 2-3 mm long. 2-4 Mexico, above 2000 m elevation. Flower- mm wade, glabrous, the 5 irregularly tri- ing from May to November. angular teeth obtuse to acute, 0.5-1 mm 324 GREAT BASIN NATITRALIST Vol. 56, No. 3

Fig. 49. Illustration of Eriogonum nealleyi slmwin^; the fjciu'iiil liiihit (A) and .i ilctail (R) of a single plant, an involiirro with flowcfs (C). and a iii.itiiic ac licrio (D). I 32' Septonihcr 1976 HKSS. lU.VEAL: RKNISION OI' ERIO(,C)N' ' M long, the bractlets linear-obhniceolate, 1.5- Watson) since the inflorescence branching 2.5 mm long, minutely glandular, the develops in the axils of the upper leaves pedicels 2-6 mm long, glabrous; flowers and not in the axils of the bracts as in white to greenish white with a green or the Ganysma (sensu Watson) group. red midrib and base, 1.5-2 mm long in We have placed Eriogonum nealleyi in anthesis. becoming 2.5-3 mm long and the section Astra. In certain characteristics pinkish to reddish in fruit, glabrous or this species does resemble E. alatum var. sparsely strigose with widely scattered glahriusculum. especially in the glabrous hairs without, essentially glabrous within jieduncles and involucres, similar leaf except for scattered strigose hairs along })ubescence, and in having seven or more the midribs, the tepals essentially mono- cauline leaves. However, E. nealleyi is morphic, oblong to narrowly elliptic, con- much more closely related to E. hieraci- nate at the base; stanu-ns slightly exserted, folium in possessing a branched caudex 2-3 mm long, the filaments pilose basally, system, pilose filaments of the stamens, the anthers red to pink. 0.9-1 mm long; and a pandurate achene with scattered achencs greenish, maturing redflish brown. strigose hairs. The nearly glabrous condi- 4-6 mm long, 2-3 mm \\'ide, pand urate, tion throughout the stem of E.. nealleyi the upper half winged, strigose, exserted; quickly distinguishes it from the other « = 20 (Figs. 24,25, 26). species of Astra which have some stem Locally common but otherwise rare in pubescence. The similarity of habit, dry, open grassland areas and roadsides flowers, and fruits tends to suggest that in west central Texas from eastern Pecos £. nealleyi and E. hieracifolium are more Co., east to Irion Co., and north to How- closely related to one another than to the ard Co.. from 60(3 to 900 m elevation (Map Alata complex (Fig. 38). 3). Flowering from July to September. Of all the species of sections Astra and Alata, Eriogonum nealleyi occurs at the Representative collections: UNITED STATES: lowest elevation (between 600 and 900 m) TEXAS: Coke Co.: Bronte. 1 .lul 1916. Palmer 10351 (ds. mo, us). Howard Co.: N of Big and in the most xeric conditions. It is easy Springs. 11 Jun 1900, Eggert s.n. (mo). Irion to speculate that the origin of E. nealleyi Co.: 3 mo S U.S. Hwy. 67 on Tex. Hwv. 915. might be from populations of E. hieraci- 9 Jul 1966, Hess 7S6 (okl); Aug 1890. Nealley folium in the mountains to the west. After 201 (cs, Ksc, neb); 9 mi W Mertzon. 2 Sep 1967, Reveal & Davidse 901 (ariz. bry, cas, the establishment of E. nealleyi and E. COLO, cs, DS. GH, ISC, KSC. LL, MO, NY. RM, hieracifolium in the disturbed habitats and rsa. smu, TEX, uc. US, UTc) . Sterling Co.: Hills along with the varied environmental con- in Sterling Count}'. 2 Sep 1925. Tharp 3373 ditions, convergent evolution could have (us). taken place in which characteristics simi- This species has a very limited distribu- lar to those in E. alatum var. glahriuscu- tion and the populations seen by us were lum developed. In addition to sharing very small, consisting usually of only a these characteristics with var. glahriuscu- few hundred individuals. The rareness of lum. the}" are also somewhat similar in this species is also evident by the absence their habitat preference, although var. or paucity of specimens in the various her- glahriusculum is found a little higher up baria w^e have visited. The type area is and consequently in slightly less xeric supposedly in Pecos County, Texas, but regions. we have seen no other collections from this part of Texas, and the label data may IV. Eriogonum sect. Alata be in error. Eriogonum Michx. subgen. Pterogonum (H. Coulter stated that Eriogonum (1890) Gross") Reveal sec t. Alata Brnfh. in DC. Prodr. nealleyi belonged in what we call the 14: 6. 1856. Species lectotvpus: E. alatum Torr. subgenus Ganysma and suggested that it in Sitgr., vide Reveal in Gunckel. Curr. Topics Sci. 243. 1969.— Sect. Alarium Kuntze in was closely related to E. ciliatum and E. PI. Post & Kuntze. Gen. Phanerog. 204. 190.3. atroruhens—following, no doubt, the prac- tice of Watson (1877) in separating those Tall, erect monocarpic perennial herbs species associated wath E. atroruhens from arising from a deep rootstock, glabrous to those more closely related to E. alatuni. silky-pubescent; leases basal and cauline, However, we believe he erred in this linear-lanceolate to oblanceolate or spathu- finding as E. nealleyi seems more closely late, glabrous to densely' pubescent; related to the members of Alata (sensu hracts ternate, mostly scalelike, connate 326 GREAT BASIN NATURALIST Vol. 36, No. 3

at the base; inflorescences elongated, open, ducing a new flush of leaves for an in- paniculate cymes; peduncles stoutish; determinate number of consecutive years; involucres turbinate to campanulate, the leaves basal and cauline, the basal leaf- 5 teeth mostly acute to truncate, the bract- blades linear-lanceolate to lanceolate or lets linear-oblanceolate, glabrous or slight- oblanceolate to spathulate, (3) 5-20 cm ly ciliated, the pedicels glabrous; flowers long, 0.3-2 cm wide, strigose to glabrous, yellowish, the tepals glabrous; anthers often slightly more strigose above than be- yellow to red; achenes winged the entire low, the margin ciliate, the apex obtuse or length of the fruit, glabrous. acute, the base long cuneate to a slightly The basis for this section is the growth winged petiole, the petiole 2-6 cm long, habit of its single species, Eriogonum ala- mostly strigose, the petiole-base scattered tum. The plants of this species form a basal strigose to densely woolly without, stri- rosette of leaves which remain vegetative gose to mostly glabrous within, the cauline for two to five or more years before a flow^- leaf-blades alternate, linear-oblanceolate to ering stem is produced. Once the plant lanceolate, 1-9 cm long, sparsely strigose flowers, it dies. These basal rosettes arise to glabrous on both surfaces except for the from a single, deep taproot, a very dif- strigose and ciliate midvein and margin, ferent habit from the branched caudices the apex acute to slightly obtuse, the base of the species in other sections of Ptero- tapering to a short, narrowly winged pe- gonum. The monocarpic nature, which we tiole, often wdth numerous, smaller axil- speculate to represent a most advanced lary leaf-blades at the base of the petiole- evolutionary stage within the subgenus, base; stems erect, 2-13 dm high, densely has strongly influenced our evaluation of to slightly strigose at the base and be- the section Alata and, consequently, typ- coming scattered strigose to glabrous near ifies this unique taxon. The section forms the inflorescence; inflorescences open pa- a close association with the section Astra niculate cymes, the branches occurring in that both groups have cauline leaves, from the base of the plant upwards, but and the ternate bracts are restricted to the mostly restricted to the upper half of the inflorescence branches. plant, 2-10 dm long, sparsely strigose to The winged achenes of Eriogonum glabrous; bracts foliaceous and scalelike, alatum are the most pronounced in the the foliaceous ones restricted to the base subgenus. In the genus overall, the of the secondary branches along the main achenes may be angled at the beak, but axis, 2-9 mm long, linear to linear-lanceo- only in subgenus Pterogonum are the late, strigose to glabrous, usually only one angles accentuated into distinct ridges or per node, the scalelike bracts restricted to wings. Because the margins of the fruit the remaining nodes, ternate. 0.8-5 mm distinct form and nearly membranaceous long, triangular to linear, strigose to gla- wings in Alata, we choose to mark this as brous without, usually glabrous within, an evolutionarily advanced condition over connate at the base; peduncles erect, the partially winged state of the other slender, straight or curved, 0.5-3.5 cm species of Pterogonum. long, sparsely strigose to glabrous; involu- Likewise, the pale yellowish color of cres turbinate to campanulate. 2-4 (4.5") the flowers is unique for Pterogonum. So mm long and wide, strigose to glabrous it seems, then, that Eriogonum alatum without, glabrous within except for the exhibits a series of features which dis- ciliated margins in some, the 5 acute tinguishes it from all others, not only in to triangular teeth 1-1.8 mm long, mostlv Pterogonum but in Eriogonum as well, erect or onh' weakly ascending, the bract- and we propf)se therefore the monotypic lets linear-oblanceolate, 2-3 long, section Alata for the species. mm glabrous or slightly ciliate, the pedicels 2-6 nun long, glabrous; flowers yellow 10. Eriogonum alatum Torr. in Sitgr. to yellowish green with a dark redilish green or reddish lirowii midrib and base, Tall, erect monocarpic herbaceous per- 1.5-2.5 null long in .nithesis, becoming ennials 5-20 (26) dm high from a deej), 3-6 mm long and reddish in fruit, glabrous chambered, soft, woody taproot; rosettes without and essentially so within, the basal, of ascending leaves, f)ersisting tepals essentiallv mononiorphic. mostly throughout the growing season and pro- lanceolate; stamens slightly exserted, 1.5- Septonibor 1976 HESS, REVEAI,: RIAlsTON OI' ERIOCJONUM 327

Fig. 50. Illustration of Eriogonum (datum, showing tlie general liabit CA), a detail of a single plant with a chambered taproot (B), an involucre and flowers (C), and a mature achene (D) of var. alatum; and a leaf-blade (E) of var. mogollense; plus an involucre with flowers (F) and a mature achene (G) of var. glabriusculum. 328 GREAT BASIN NATURALIST Vol. 36. No. 3

3 mm long; the filaments glabrous, the var. mogollense, and var. glabriusculum. anthers yellow to red, 0.4-0.5 mm long; The two non-typical forms have a restrict- achenes yellow to yellowish green ma- ed distribution, and are easily defined. turing reddish brown, short stij)itate, 5-9 However, within the concept of var. mm long, 3-6 mm wide, glabrous, distinct- alatwn, there are additional forms which ly 3-winged the entire length of the fruit, have been described and are strikingly exserted; n = 20 (Figs. 27-33). different but seem to fail to reflect any Common in grasslands of the Great particular distribution pattern. In var. Plains and in the pinyon-juniper wood- (datum there are both densely strigose and lands and ponderosa pine forests of the weakly strigose plants; leaves that are Rocky Mountains from northern Chihua- nearly linear and leaves that are much hua, Mexico, northward in the Great broader; plants which branch from near Plains to Nebraska and Wyoming, and in the base of the stem to the top, and others the Rocky Mountains to Utah and Colo- which branch only on the upj)er half of rado, from 300 to 3100 m elevation (Map the plant. All of these phases are indis- 4). Flowering from June to October. criminately scattered throughout the This poljTTiorphic species, which has re- general range of the t3pical variant, or sulted in the separation of several infra- they may be found in scattered locations. specific variants, has a wide range of dis- Because of these field data, we have de- tribution. We recognize three: var. alatum. cided not to further subdi\ade var. alatum.

Key to the Varieties of E. alatum

A. Plants strigose throughout or occasionally sparsely strigose on the peduncles with glabrous involucres; inflorescences mostly developed from the basal nodes through the upper nodes; stems and inflorescences 10- 17 dm tall; common in the Rocky Mountains and Great Plains southward to northern Mexico. B. Basal leaves 0.3-1.5 cm wide, linear-lanceolate to lanceolate or oblanceolate; petiole-base strigose; widespread and conunon throughout the range of the species 10a. var. alatum BB. Basal leaves 1-2 cm wide, spathulate; petiole-base woolly; local in forests around Flagstaff, Arizona 10b. var. mogollense

AA. Plants glabrous or slightly strigose in the inflorescence and rarely with strigose peduncles; inflorescences mainly developed in the upper nodes; stems and inflorescences 10-25 dm high; common in the southern Great Plains of north central Texas, and western Oklahoma and rarely northeastern New Mexico 10c. var irlahriusculum.

10a. Eriogonum alatum \ar. alatum Isotypes: c..\s, isc, k, mo. ny, uc, us! Eriogo- num alatum Torr. in Sitgr. ssp. triste (S. Figs. 50a, b, c, d. Wats.) S. Stokes, Gen. Eriog. 20. 1936. Eriogonum alatum Toit. in Sitgr.. Rep. Exped. Eriogonum alatum Torr. in Sitgr. var. hrerifolium Down Zuni and Colorado Rivers 168. 1854. Gand.. Bull. Soc. Roy. Bot. Belgique •^2: 186. —Near Zuni, McKinley Co.: New Mexico, 25 1906.- I.aramie Hills, Albany Co.. Wvoming, Sep 1851. Woodhouse s.n. Lectotvpus ny! — 29 .lun 1896. E. Nelson 19S9. Holotype: ly! Pterogonum alatum (Torr. in Sitgr.) H. Gross, Isotypes: bm. cs. ksc, mont, rm! Bot. .Tahrb. Syst. 49: 239. \9\'i.--Eriogonum Tall, erect perennial herbs 5-13 (17) alatum Torr. Sitgr. ssp. typicum S. Stokes. Gen. Kriog. 20. 1936. (hn high; leaiws basal, infrocpiontly cau- Eriogonum alatum Ton-, in Sitgr. var. vlatum line, the basal leaf-blades linear-lanceolate Geyer ex Benth. in DC, Froth-, 14: 7. 1856. to lanceolate or oblanceolate, (3) 5-15 cm —-"On trap rock.s, opposite tlie Red Butter long, ()."5~1.5 cm wide, strigose or glabrous [sic, Buttes], between Platte and Swect-watei- for mar- Rivers, on banks of deep and ferruginous except tlie strigose midvein and loam," Natrona Co., Wyoming. .Tun or Jul gin, the petiole 2-5 cm long, the petiole- 1843, Geyer 145. Holotype: k! Isotypes: bm, base s[)arsely strigose to strigose. the cati- E, g! line leaf-blades l-() cm long; inflorrsrrnccs Eriogonum triste S. Wats., Proc. Amer. Acad. Arts thinh' strigose. infre()uentl\ glabrotis at 10: 347. 1875.- Likely from near Kanah, Kane Co.. Utah, 1874. Siler 147. Holotype: gh! iiwitiirity, 2-10 (bii long; pcdutich's stri' J "-

Septcniher 1976 IIF.SS. RKVKAL: HIAISION OI' KHKXJONLTM 329 gose or nearly so; involucres strigose to rado Sprmgs. 25 Jul 1884. Letterman s.n (mo) rarely glabrous without, Sanguarhe the teeth acute Co.: Junct. of 114 S of US Hwy or obtuse; 50. Jul achencs 5-8 mm long. 3-() 13 1963. Dunn & Willey 14556 mm fuMo). wide; Az = 20 (Figs. 27, 28). Teller Co.: 2 mi S Florissant.' 16 Aug ^96\ Ufis & litis 18735 (wis). KANSAS: Rus Common in sandy to sell gravelly places in Co.: 4 mi N Russell. 6 Jul 1959, Jackson open 139 grasslands or among pinyon-juniper (kans). Scott Co.: 14 mi N Scott City 28 Aug woodland or pine forests of 'the 1957. McGregor 13643 (kans) NE- Rocky BRASKA: Banner Mountains from Utah and Co.: SW Harrisburg 17 Arizona across Jul 1968. Stephens & Brooks Colorado and New 24801 (kans). Mexico into the Great Cherry Co.: Near Hackberrv Lake, Jun 1912 Plams from southwestern Doorak s.n. (neb). Nebraska anrl Chevenne Co.: 1 mi E l' adjacent Wyoming to northern Me.xico V'A^ ^''"""^- ^^ ^"S ^967, Stephens & Brooks 16048 (kans). Deuel from 1350 to 51()() Co.: McColligan Canyon. m elevation. Flowerinu 22 Aug 1891. Rydberg 330 (..\riz. neb, ny) from .Tune to October. Kimball Co.: 1.5 mi W Di.v. 27 Jul 1971 Stephens 50127 Hf.present.vtive (kans). Morrill Co.: 4 mi N collections: MEXICO: Chiliua- Broadwater, hua: Gnayanopa 12 Jul 1967. Stephens & Brooks Canyon. Sierra Madre Oc- 13914 (K.ANS). Sep Scotts Bluff Co.: 8.5 mi W "/l?nlal. 24 1903. M. E. Jones s.n. (ny) NITED STATES: ™"^- ^'^ ^"^ ^^''O. Stephens & Brooks ARIZONA: Apache Co.' 43993 (kans). NEW MEXICO: Luka-Chukae Mts., 9 Aug Bernalillo 1939, Goodman & Co.: Manzano Mts.. Parson 3 6.2 mi S U.S Hwy 66 i 89 (isc. mo, ny). Cochise Co.: Mus- along N.M. Hwy. 14, 24 Aug 1973. Holmgren tang Mts., 28 Jun 1884. Pringle s.n. (br e & Holmgren 7379 (bry, ny, unm). G. GH NY, OKL, us). Catron p, Coconino Co.: Near Co.: 4 mi S Beaverhead Ranger Jacob Lake. 4 Aug Station 18 1967, Gentry & Davidse Aug 1966. Hess 1797 (NY 879 (.\riz. okl). Colfax Co uc, UTC, WTU). Gila Co.: Near Black Raton Pass. 27 Jun 1971. Godfrey 70566 (fsu) River, 28 Jul 1965. Hess 353 (..riz. okl) DoBaca Co.: 8 mi E Yeso, 12 Graham Co.: 6 mi Aug 1947 W Point of Pines ^4 Jul Waterfall 7730 19d2. Bohrer (gh). Eddy Co.: Guadalupe 425 (.ariz). Greenlee Co.': Below Mts., 19 Oct 1939, Barneby 2585 (ny). Grant Sardine Saddle 24 Jul 1973, Lehto et al. Co.: Near Tyrone. 9 Aug 1968. Gentry 11262 Usv). Mohave Co.: & Toroweap Valley Jensen 2277 (asu, 10 May cs, ds, ids. isc, ksc ny 1952, McClinlock 52-517 (^mz) osc. Navajo TEX, UTC, WTu). Hidalgo Co.: Indian Cr Co.: 19 mi NE Show Low, 29 Jul 1965 Hess Animas Mts., 7 Oct 1967, Hess 1552 (smu) 571 (.ARIZ, duke, okl. tex. uc). Pima Lincoln Co.: 3 mi E Nogal. 25 Jul Canjôn. Sep 1965. Hess 4^^?""^ 15 1958, Goodding 302 (.ARIZ. okl. tex). 488-58 (ariz). McKinlev Co.; Chaco Yavapai Co.: Near Prescott 8 Canyon, May 1937. Hastings s.n. (.ariz). Mora Co.: 1 mi NW Wagon Alamosa Mound. 30 Jul 1968 Co.: N of Alamosa. Stephens & Brooks 26171 28?«^^^SSÂug 196/. (kans). Otero Co.- Lewis s.n. (asu). Archuleta Co.- Pagosa 12.5 mi S Mescalero, 24 Jul 1965. Hess 294 Springs. 12 Jul 1899. Baker 283 (bm (ariz, okl). Rio Arriba Co.: 44 mi N Espafi- ^ô"lder Co.: lo'"/"' ''Tnô^'.y'^- Horse Mesa. ola along U.S. Hwy, 84. 22 Jun 1913, Ramaley 3 Jul 1970. Higgins 9600 (colo). Chaffee 3584 fBRY. wTs). Co.: 4-3 Sandoval Co.: Sulphur m SW Trout Creek Pass. 2 Jul 1959 Springs. Russell 17 Aug 1926. Arsene & Benedict 10115 (cs). Clear Creek Co.: Idaho 16440 (isc). San Miguel Co.: Gallinas Springs 17 Aug 1923, Pammell & River Jeffers s.n Valley. 11-17 Aug 1945. Lundell & Lundell ^°-^ - "" E Westcliffe. 3 Aug Vn^}- c?"'!^"" 14494 (ll). Santa Fe Co.: Canoncito. 12 Jul 1968, Stephens & Brooks 26693 (kans) Delta 1926. Arsene & Benedict 15913 (p). Socorro ^ Cedaredge. 31 h?-^z. ^L^^"^' May 1952. Co.: Chupadera Mesa. 11 Weber 7575 (colo). Aug 1948. Dunn & Douglas Co.: Buffalo r.vit 4339 (uMo). Taos Co.: Near Tres Ritos. Creek, 4 Aug 1933, Goodman 1997 (gh isc 16 Aug 1946, Martin 1064 (wtuV Torrance ""'"^- ^^ P^s" Co.: Mantou. 18 t''^- r?o.°''^'^- Co.: 2 mi NW Monzano, 4 Aug 1949. Dunn Jul 1886. Bessey s.n. (neb). Fremont Co- 8 6163 (kans. umo). Union Co.: 32 mi W Clay- ^^^''^- "> J"^ ^^^54. Harrington ^'^'oo T'^-:^''. ton. 24 Aug 1966. n22 ?fcs). Hess 976 (.ariz, okl). Va- Gilpm Co.: Near Pine Cliff 13 Jul lencia Co.: Mt. Sedgwick. Zuni Mts.. 17 Aug ^^^^-^ ^^'^^- Huerfano Co.: )SiJr-r^""'-l 16 m> 1968. Riffle 811 (unm). TEXAS: Brewster ^ ^"g 1^68- Stephens 8z Brooks 26660Vz!^.^^'"'^"'^'"- Co.: Green Vallej-. Glass Mts.. 23 Jul 1940. (kans). Jefferson Co.: Morri.son. 1877 Warnock W5 (ariz, isc. tex, us). Culberson Hooker & Gray s.n. (k). Kit Carson Co.:" Co.: Near Frijole. 30 Jul Without location, 1930, Grassl 182 Aug 1890. Harris s.n. (ill) (.\Riz). Dallam Co.: T^nknown location. 8 Aug La Plata Co.: 5 mi W Durango. 4 Aug 1965 1891. Carleton 397 (cs. Hess 469 (ariz. ksc. osc). Hudspeth okl). Larimer Co.: 3.5 mi S Co.: 0.5 mi N McAdoo Ranch, Sien-a Diablo 21 Aug 1970. Stephens & Brooks 42769Âi^fJ^""^- Mts.. 29 Aug 1949. Hinckley & Hinckley 308 (KANs). Mesa Co.: 6 mi S Fruita. 22 (kans. smu). UTAH: Carbon Co.: Tavaputs May 1948. Weber 3892 (ariz, colo. tex Plateau, 19 Jun 1965. Holmgren et al. 1961 /)^°"\^^"™^ C"- ^ "li E Cortes, 9 Sep I n'^'^- • TaRIZ. BRY, CAS. COLO, CS. DS, GH, ISC. KSC. MO. j968 Howell & True 45005 (cas). Montrose NCU, NY. OKL, OSC. RENO. RM. RSA, SMU. TEX, Co.: 18 mi E Naturita. 15 Jul 1935. Maquire Piranian UC, US, UT. UTC. WIS. ws, wTu). Daggett Co.: & 12439 (uc). Ouray Co.: Ourav. 12 mi S Manila. 16 Aug 1935. Maguire al. II Jun 1969, Atwood & Higgins et 1822 Cbry). 12655 fcH. utc). Duchesne Park Co.: Spruce Grove Co.: 18 mi W Du- Campground. 5 Aue chesne. Jul 1971. 5 1947, Ferris 11312 (cas. ds. utc. Pmkava 8932 (asu). Pueblo Co.: Colo w-Tu). Emerj- Co.: 27 mi W Green River. 25 330 GREAT BASIN NATURALIST Vol. 36, No. 3

May 1961. Cronquist 9i04 (ny). Garfield Co.: dividual plants which vary from densely 7 mi E Escalante, 2 Jun 1948, Holmgren 7727 strigose to nearly glabrous even in a single (cAS, uc, UTc, ws, WTu). Grand Co.: Moab. population. 9 Jul 1913. M. E. Jones s.n. (pom). Iron Co.: We have seen var. alatum in Near Cedar Breaks Natl. Mon., 2 Sep 1936. the field throughout most of its range and Gierish s.n. (utc). Kane Co.: 10 mi N Glen- have examined innumerable herbarium dale. 18 Jul 1940. Maguire 19661 (nv, utc). specimens. We prefer a more conservative San Juan Co.: Comb Reef, 20 Jun 1944. treatment because of the Holmgren & Hansen 3414 (ariz. gh. ids. ny, wide morpholog- osc, uc, us, UTC, ws). Sevier Co.: 31 mi S ical variation and lack of any consistent Emery, 22 Jun 1961, Cronquist & Holmgren geographical associations found in the 9525 (ny, utc, ws, WTu). Co.: Uintah 46 mi various forms aligned with var. alatum. SE Ouray, 27 Jul 1965, Holmgren et al. 2273 (ariz, bry, cas, colo, cs, ds, gh, mo, The center of distribution for var. ny, okl, osc, reno, rm, rsa, tex, uc, us, utc, alatum would seem to be the southwestern WTu). Utah Co.: P. V. Junction, Aug 1883, United States, perhaps in the Mogollon M. E. Jones s.n. (ds, pom). Washington Co.: Mountains of New Mexico. Here the popu- Hurricane, 17 Jul 1925, Kraus s.n. (wis). Wa- satch Co.: Strawberry Reservoir, 22 Jul 1948. lations mostly occur in relatively undis- Ripley & Barneby 9946 (cas). Wavne Co.: turbed areas, whereas farther north the 30 mi Boulder, 2 N Aug 1965, Hess 423 populations are more common along dis- (ariz, okl). WYOMING: Albany Co.: Sheep turbed sites such as road cuts, erosional Mtn., 2 Sep 1903. Goodding 2108 (gh, ny, us). Carbon Co.: Platte River, 9 Jul 1894, cuts, and canyon breaks. Its migration Nelson 416 (ny, rm). Goshen Co.: Raw Hide would seem to be northward in the moun- Buttes, 23 Jul 1909, Cory 378 (us). Laramie tains and onto the Great Plains via water- Co.: Cheyenne, 11 Aug 1891, Nelson IS (gh). ways. With such a broad distribution and Niobrara Co.: 3 mi S Manville on Wvo. Hwy. 270, 11 Aug 1975, Hess 3542 (mor). Platte the diversity of available habitats, certain Co.: Guernsey Lake State Park, 11 Jul 1946, morphological features (i.e., short leaves, C. L. Porter 4011 (ds, gh, kans. rm. uc. wtu). glabrous condition) have become estab- Sweetwater Co.: 20 mi W Green River near lished. However, no discernible patterns Little America, 17 Sep 1961. Mason 4034 (asu, bry, osc). have been consistent, and as a result var. alatum is quite variable, perhaps with In the subgenus Pterogonum, the dis- ecotypes in their early stages of evolution- tribution of var. alatum is the most ex- ary development. tensive. Within this broad geographical range there are numerous minor phases Plants intermediate between var. alatum var. fovnid in which have, in the ])ast, been noted as dis- and glahriusculum were tinct. Ecological conditions most likely ac- Union County, northeastern New Mexico, count for this variation since the plants of on the canyon breaks above Tramjieros var. alatum may occur within ponderosa Canyon (Hess 976) . This has indicated a pine forests, grasslands openings within possible pathway for the movement of cer- the forests, in the grasslands of the north- tain members of this species onto the ern latitudes, or in the quite xeric areas Great Plains. With the follo\^^ng isolation restricted dis- on exposed limestone with scattered ])in- and selection within a more yon-juni})er as seen in parts of Utah and tribution, a polymorphic taxon of Eriogo- northern Arizona. The plants in Wyo- iium aUitiun could result. ming and adjacent western Nebraska have been called var. elatum (and later, var. 10b. E.riop,onum alatum var. mogollense brevifolium) and are characterized by Stokes ex Jones short, narrow, basal leaves. The occur- Fig. 50e. rence of this kind of leaf shape, however, Eriognnum alatum Torr. in Sitgr. var. mogol- is widely scattered, and plants which re- lense Stokes ex .loiios, Contr. W. Bot. 11: 15. semble those of var. elatum are foiitid 1901 -Flagstaff, Coconino Co., Arizona. 7 Aug throughout the general range of \ar. 1884. M. /','. Jones 3975. Lectotype: pom! Iso- lectotypes: ariz, bm, br, cas. ds, g, gh. ny, alatum. Those plants considered to be p, uc, us. utc! —Eriogonum alatum Torr. in oc- Erioponum tristc are more restricted, Sitgr. ssp. mogollense (Stokes ex Jones) S. curring primarily in southern Utah and Stokes, Gen. Eriog. 20. 1936. northern Arizona. They have a tendency F.ringonum alatum Torr. in Sitgr. var. mac- toward a glabrous condition, but again ilnugalii Gand., Bull. Soc. Rov. Bot. Belgique 42: 186. 1906. -Near Flagstaff. Coconino Co., this feature can be seen in other popn Arizona. 8 Jul 1898. MarDougal 259. Ilolotype: lations beyond the range noted alxne. i,y! Isotvpes: hki,. e. g. gh, i.sc. ny, p. ph, UC, Even in Utah and Arizona there are in- us! Sci)toni])er \97G III.SS. HF-VEAL: lUAIMON OI' I-,HI()(;(>N r M 331

Tall, erect pereiniinl herbs 8-13 dm 10c. Eriogonum alatum var. glahriusculum high; leaves beisal and cauliiie, X\\v basal Torr. in Wliipple

leaf-bhules spatliulate, 4-11 c ni loiig, 1-2 Figs. 50f, g. cm \vi(]e. strigose above, ghibrous below Kriogonurn alatum Torr. in Sitgr. var. glabrius- excej)! for strigose midvein and margiTi. riiliim Tori\ in Wliipple, E.xplor. & Sui"v. the j)etiole 4-6 cm long, the petiole-base Railroad Route from Mississippi River to Pa- densely ])n)\vn woolly, the cauline leaf- cific Ocean 4: 131. 1857. High places near the Canadian River, Roger Co., Oklahoma, blades 1-5 cm long; inflorescences strigose, Mills 3 Sep 1853. Bigelow s.n. Holotype: ny! Iso- 2-6 long; strigose; involucres dm peduncles type: us! strigose without, the teeth mostly acute, the bractlets ciliate; achcnes 5-8 mm long, Tall, erect perermial herbs 10-20 (25) (4) 4.5-6 mm wide; /2-20 (Figs. 29. 30, dm high; leaves basal and cauline, the 31). basal leaf-blades linear-lanceolate to lanceolate, 8-20 cm long, 0.5-1.5 cm wide, Common in open pinyon-juniper and slightly strigose or glabrous above, gla- ponderosa pine forests in and around the brous below except for the strigose mid- Magstaff area of Coconino Co., Arizona, vein and margin, the petiole 2-5 cm long, northward to the south rim of the Grand the petiole-base slightly strigose without, Canyon, and eastward on the Mogollon the cauline leaf-blades 1-9 cm long, 0.3- Plateau to north of Show Low, Navajo 0.9 cm wide; inflorescences glabrous, 2- Co.. Arizona, from 18(J() to 2500 m eleva- 6.5 dm long; peduncles glabrous or oc- tion. Flowering from June to September. casionally slightly strigose; involucres Represent.^tive COLLECTIONS: ARIZONA: Coco- glabrous without, the teeth obtuse or trun- nino Co.: Flagstaff: 29 Jul 1910, Adams s.n. cate, the bractlets glabrous; achenes 5.5- (wis); 22 Aug 1941. Denver 429 (asc); 8 Aug 9 mm long, 3-5.5 mm wide; ^2 = 20 (Figs. 1922. Hanson A183 (neb. osc. tex); 14 Aug 32, 33). 1920. Thornber s.n. (ariz, taes) ; 28 Jun 1935. Whiting 75^/870 (mna); 1 mi N of S en- Common in the grasslands along can- trance to Grand Canyon N.P., 25 Jul 1961. yon breaks from Curry Co., New^ Mexico, Harrington 9639 (cs) ; 23 mi N Payson. 23 eastward across northern Texas to western Aug 1966. Hess 96i (..\riz. okl); NW of Flag- staff, 18 Aug 1973. Reveal & Reveal 3225 Oklahoma, from 500 to 1400 m elevation. (bry. NY, us). Navajo Co.: 9 mi N Heber. 4 Flowering from July to October. Jul 1965, Pinkava 2320 (asu). Representative collections: NEW MEXICO: The plants of var. mogollense are re- Curry Co.: Along Frio Draw, neai- Ruth, 27 stricted in distribution to the mountains Jul 1939, Reynolds 242 (neb). OKLAHOMA: Reckham Co.: 21 Sayre, 10 1927, around Flagstaff. Arizona, and eastward mi N Aug Stratton 364 (mo). Ellis Co.: Near Shattuck. 11 the to on Mogollon Rim southwestern Oct 1913, Stevens 2938 (ds, gh. k, mo. ny, Navajo County. This variant may be char- OKL, us). Garvin Co.: 2 mi S Purdy. 24 Sep acterized by its spathulate basal leaves 1966, He.^s & Harrison 984 (.'vriz. okl). Roger and woolly petiole-bases. Otherwise, the Mills Co.: 6 mi SE Cheyenne, 21 Aug 1950, Goodman & Kelting 5404 (kans, ny, okl, plants are similar to var. alatum. Popula- tex). Stephens Co.: 6 mi W Foster. 24 Sep tional analysis of the plants in the Flag- 1966, Hess & Harrison 985 (okl). Woodward staff area predominantly shows the spath- Co.: 8 mi SW Woodward, 20 Jul 1934. Good- 2i80 (lsc, mo, okl). Armstrong ulate leaf character. It would seem that man TEXAS: Co.: 15 mi S Claude, 23 Aug 1967. Reveal no or little movement of genes controlling & Davidse 879 (ariz, bry, cas, gh, mo, ny, the leaf-.shape has occurred in this area; rm, rsa, uc, us, utc). Briscoe Co.: Tule Can- therefore, the spathulate leaf character has yon. 24 Aug 1967, Reveal & Davidse 880 (ariz. bry. cas, gh, LL. mo, NY, RM, RSA, SMU, been maintained. However, it is difficult TEX, TTc, US, utc). Carson Co.: 3 mi NW to determine if there is a populational Skellvtown, 27 Aug 1967, Stephens & Brooks

change in the frequency of plants with 17i50 (kans). Childress Co.: Childress, 1 Oct spathulate leaves as opposed to those with 1932, Tharp s.n. (tex). Crosbv Co.: 3 mi E 1964. Hanson (ll, lanceolate leaves. Although plants ap- Crosbyton. 29 Jun 479 tex, us). Dickens Co.: Between Croton and proaching the morphological characteris- East Afton, 10 Aug 1972, Higgins 6092 (bry, tics of var. mogollense occur elsew^here. it WTs). Donlev Co.: Betw^een Clarendon and seems reasonable to recognize var. mogol- Brice, 8 Sep 1934, Reed 4087 (tex). Floyd Co.: Plainview Road. 23 Aug 1921, Ferris &

I lense due to the constancy of its morpho- Duncan 3366a Tmo. ny). Grav Co.: 15 mi SE logical characteristics associated with its Pampa. 3 Aug 1966, Hess 761 (okl). Hall

I limited range. Co.: Brice. 8 Sep 1934. "collector unknown" 332 GREAT BASIN NATURALIST Vo. 36, No. 3

4087 (ttc). Hemphill Co.: 6.7 mi NE Cana- PLngelm.\nn. G. 1848. Botanical notes. In: F. A. dian, 28 Sep 1935, Parks & Cory 161S2 (t.\es). iWislizenus. Memoir of a tour to northern Hutchinson Co.: 7 mi from Adobe Wall site. Mexico, connected with Col. Doniphan's ex- 28 Aug 19&K Correll & Correll 5001t (ll). pedition, in 1846 and 1847. Tippin & Streeper, Lipscomb Co.: 1 mi N Lipscomb, 21 Sep Printers, Washington, D.C. 19:58, Wallis 7956 (smu. tex). Lubbock Co.: G.\NDOGER, M. 1906. Le genere Er logon um Lubbock, s.d.. Reed 5106 (us). Motley Co.: (Polygonaceae). Bull. Soc. Roy. Bot. Belgique Roaring Springs. 26 Sep 1935, Parks & Cory 42: 183-200. 15977 (t.-^es). Ochiltree Co.: 12 mi SE Perry- Geiser. S. W. 1948. Naturalists of the frontier. ton, 20 Sep 1958. Wallis 7883-i (duke, smu, 2nd ed. Southern Methodist University Press, TE.x). Randall Co.: Canyon, 3 Oct 1918, Palmer Dallas. 14587 (bkl, mo. NY, wis). Roberts Co.: 27 mi Goodman. G. J. 1934. A revision of the North S Perryton, 19 Sep 1958, Wallis 7843 (t.\es, American species of tlie genus Chorizanthe. tex). Ann. Missouri Bot. Gard. 21: 1-102.

. 1945. Author citation for Eriogonum The trends in var. glabriusculuni are hemipterum. Rhodora 47: 92. easily distinguished when populations are Gross, H. 1913. Beitrage zur kenntnis der Poly- gonaceen. Jahrb. 234-339. examined. Many plants are over 1.6 ni Bot. Syst. 49: Hess, W. J. 1967. A ta.xonomic study of the tall, and heights of 2.5 m are known. The subgenus Pterogormm in the genus Eriogonum basal leaves are generally long and nar- (Polygonaceae). Unpublished doctoral disser- row, with less ])ubescence than those of tation, University of Oklahoma Library, Nor- the other varieties of the species. The in- man. Oklahoma. Holmgren. P. K., and W. Keuken. 1974. Index florescence branching is restricted to the horbarioi-um. Part L The herbaria of the upper nodes of the stem and is not devel- world. 6th ed. Regnum Veg. 92: 1-397. oped from the bottom nodes as is common .loHNSTON, L M. 1944. Plants of Coahuila. east- in var. alatum and var. mogollense. For ern Chihuahua and adjoining Zacatecas and Durango, V. J. Arnold Arbor. 25: 133-182. the most part, the involucres and pedun- Jones, M. E. 190 3. Eriogonum. Contr. W. Bot. cles are quite glabrous and the remaining 11: 4-18. branches of the inflorescence are glabrous McKelvey. S. D. 1955. Botanical exploration of or with scattered pubescence. The involu- the trans-Mississippi west. 1790-1850. Arnold Ai'boretum. Jamaica Plain. Massachusetts. cral lobes are not sharply pointed but are Post. T. von, and O. Kuntze. 1903. Lexicon often irregular or truncate. These trends generum phanerogamarum. Published by the in populations of var. glabriusculuni tend authors. Stuttgart. Reve.\l, J. L. 1967a. Notes Eriogonum - IL to place it apart from the other varieties. on • Variation in Eriogonum atrorubens. Sida 3: In Oklahoma and Texas, var. glabrius- 82-86, culum is most often found on slightly fhs- . 1967b. Eriogonum. ///: Documented turbed ground at the edges of canyons chromosome numbers of plants. Madrono 19: 134-136. and gullies. The occurrence of this vari- . 1968a. Notes on Eriogonum - IV. A ant on the breaks suggests a pathway of revision of the Eriogonum defloxum complex. distribution from the Rocky Mountains Brittonia 20: 13-33. onto the Great Plains as mentioned before. . 1968b. Notes on the Texas eriogonums. Sida 3: 195-205. Incipient speciation may occur with the . 1969a. The subgem-ric concept in Erio- present isolation if the morpbological dif- gonum (Polygonaceae) . Pages 229-249 in ference of var. glabriusculurn and var. .r. Gunckel, ed. Current topics in plant alatum are genetically controlled. This science. Academic Press. New York.

. J 969b. revision of the genus Erio- would be speculation, and since \ar. A gonum. Unpublished doctoral dissertation, alatum is quite variable, including some Brigiiani Young T University Librar^'. Provo, infraspecific characteristics conmion to I'tah. var. glabriusculum. consideration of the 1970. Kriogoiium. Pages 510-516 in I). S. C()rrell and M. C. Johnston, Manual Oklahoma and Texas taxon as a \'ariety of llu' vascular- i)lants of Texas. Texas Re- seems to be the nujst reasonable. search Foundation, Reniier, Texas. Reve.m., J. L., AND J. T. HowKt.i. 1976. De- deckera (Polygonaceae). a new geims from LiTKR.ATI 'RF. C JTI.O California. Biittoiiia 28: 245-251. 1\evi-ai,. I. 1... .\rsi) i:. L. Styi.er. 1973. Miscel-

AxELROD. D. I. 1958. Evohitioii of the ma(ho- laneous I hrt)mosoiue coimts of western Ameri-

tcrtiary geoflora. Bot. Rev. 24: 433-509. can plants - II. (Jieat Basin Naturalist 33: Bentiiam, G. 1856. Rriofronitrn. In: A. d<'(,

'»() !. dolle. (kI. Prodromus syti'iiiiitis natiitaiis r-curii l^)lll.KTY. G.. ANI) S. Vautieh. I l.l'S gi'IirPS vegetabilis 14: 5-23. de F^olygonaceae. Boissieta 10: 7 128. Cour " I ^'T. 1800. Unori a collet tidu ol SrAii.EU, F. A. et al,, ed. 1972, International plants made bv G. C. Noallov. Contr. IS. code of I)otanical nonu-ndature. Regnum Veg. Natl. Herb. I: 29-61. 82: 1-426. Se[)tonil)('r 1**76 HKSS. REVEAL: REAISION OK EHIOGONITM 333

Standi.ey, p. C. 1936. Studies of Amerirnn the most practicable and economical route plants. VI. Field Mus. Nat. Hist.. Bot. Sor. for a railroad from the Mississippi River to 11: 145-276. the Pacific Ocean. 4: 59-182. A. O. P. Nich- Stebbins. G. L. i1942. Polyploid comple.xes in olson. Printer. Washington, D.C.

relation to ecology and the history of floras. . 1859. Botany of the boundary. In: W. Amer. Naturalist 76: 36-45. Emory, Report on the United States and

. 1974. Flowering plants. Evolution above Mexican boundary survey., 2(1): 27-270. C. the species level. Belknap Press of Harvaid Wendell. Printers, Washington. D.C. University". Cambridge. ToKREY. J.. .\ND A. Gr.ay. 1870. A revision of Stokes, S. G. 1936. The genus P^riogonum. a the Eriogoneae. Proc. Amer. Acad. Arts 8: preliminary study based on geographical 145-200. distribution. J. H. Neblett Press. San Fran- Watson. S. 1875. Revision of the genus Ceano- cisco. thus, and de.scriptions of new plants. Con- .Stokes, S. G.. .\nd G. L. Stebbins. 1955. tributions to American botany. Proc. Amer. Chromosome numbers in the genus Eriogo- Acad. Arts 10: 333-350.

num. Leafl. W. Bot. 7: 228-233. . 1877. Descriptions of new si)ecies of ToRRKY. J. 1854. Botanical appendix. In: L. Sit- plants, with revisions of certain genera. Con- greaves. Report of an e.xpedition down the tributions to American botany. Proc. Amer. Zuni and Colorado rivers. B. Tucker. Printer. Acad. Arts 12: 246-278. Washington. D.C. WooTON. E., AND P. C. Standi.ey. 1913. Des-

. 1857. Description of the general bo- criptions of new plants |)reliminary to a re- tanical collections. In: A. W. \\lnpple. Re- port upon the flora of New Mexico. Contr. ports of explorations and surveys to ascertain U.S. Natl. Herb. 16: 109-196.