The Leaf of Calycadenia and Its Glandular Appendages

Reprinted fmm the AMERICAN JOURNAL OF BOTANY, Vol. 16, No. -'- 70-80, February, 1959 Printed in U.S. \.

THE LEAF OF CALYCADENIA AND ITS GLANDULAR APPENDAGES

SHERWIN CARLQUIST THE LEAF OF CALYCADENIA AND ITS GLANDULAR APPENDAGES1

SHERWIN CARLQUIST

ABSTRACT CARLQUIST, SHERWIN. (Rancho Santa Ana Botanic Garden. Claremont, Calif.) The leaf of Calycadenia and its glandular appendages. Amer. Jour. Bot. 46(2) : 70-80. Illus. 1959.—Large tack-shaped glands are characteristic of the leaves of Calycadenia which are associated with the inflorescence. These glands may he divided into those which are terminal on leaves and those which occur laterally on the surface of the leaf. Lateral glands show stages early in their develop ment which are identical with those of simpler trichomes of Madinae. Terminal glands, which possess more vascularization of the stalk, show a more modified form of development. Vasculari zation is not derived from protoderm. hut from more deeply-seated cells. These cells are included in a zone of elongation which forms the stalk. Vascular bundles may extend to the base of glands which lack vascularization in their stalks. Tack-shaped glands are considered an advanced form of trichome in which internal tissues of the leaf are involved. Within the genus Calycadenia, ontogenetic and comparative studies suggest that the following characters are advanced: reduction to a single terminal gland, "inrolling" of margins to form a cylinder *>l bundles, concomitant with a central core of fibers or a pectic channel. Systematic distribution of gland occurrence and of types of foliar structure are given.

THE ''TACK-SHAPED GLANDS" of Calycadenia denia are polymorphic within a single plant. There (Compositae. tribe Helianthrae. subtrihe Madinae) fore, basal, intermediate, and upper leaves were have been recognized b\ taxonomists as a character studied for each species. The variation within a istic of that genus. Such glands occur on leaves of single plant was most carefully examined in C. the Inflorescence, particularly on those of abbrevi imiltiiilandulosu \ar. cephalotes, in which several ated shn.it- which terminate in heads, and on the leaves in each category from 5 individuals were outer surface of involucral bracts. These glands are sectioned. Liquid-preserved collections were util absent on basal leaves; they are lacking on all ap ized for C. multiglandulosa var. cephalotes and C. pendages of Calycadenia teneUa. Preliminary stud villo.su. For the remaining species, herbarium ma ies revealed that tack-shaped glands of Calycadenia terial proved quite satisfactory for anatomical pur are more complicated than those of other Madinae poses. Fresh materia] was preserved in formalin- which were described in an earlier paper (Carlquist. propionie alcohol ijohansen. 1940). Herbarium 1958). A study of the ontogeny of the glands and material was expanded l>\ treatment with warm a comparison of mature glands within the genus 2.5?5 aqueous NaOll. followed by washing and were undertaken basically to demonstrate the rela -ti'iaue iii 7i>'. eth\l alcohol. Both liquid-preserved tionship between them and the simpler trichomes and herbarium specimen material were embedded of other Madinae. Because at least some of the in paraffin according to the usual techniques. Sec tack-shaped glands of Calycadenia are not simple tions were stained according to Northern's modifica trichomes, the general term "gland" is used here. tion of Fosters tannic acid ferric chloride method On account of the fact that tissues other than epi Johansen, 1940). Leaves of Calycadenia, particu- dermal are involved in the mature gland, studies on larl) the upper ones, are mosllv subterete. Because the onloLvnv and mature structure of Calycadenia of this. 3 types of sections are distinguished here: leaves proved a necessary adjunct to studies on the transverse, sagittal (a median longitudinal section glands. of a leaf radial to the stem axis), and paradermal MATERIALS AND METHODS.—Leaves of Calyca- la longitudinal section cut parallel to the dorsiven- 1 Received for publication May 27, 1958. tral axis of the leaf). The term "lateral" is used February, 1959] CARLQU1ST—LEAF AND GLANDS OF CALYCADENIA 71

Fig. 1-8. Ontogeny of terminal glands on upper leaves of Calycadenia multiglandaiosa var. crphalotes. Fig. 1-5, 8 from sagittal sections; fig. 6-7 from paradermal sections.—Fig. 1. One-cell stage. X480.—F'g- 2. Four-cell stage (two cells in plane of section). X^OO-—Fig. 3. L Multicellular -tage. Fig. 3, X630; fig. 4, X485.—Fig. 5. Initiation of glandular layers. X1140.—Fig. 6. Formation of procambium in stalk re-:i..n. X270.—Fig. 7-8. Sections of mature glands. X180. 72 AMERICAN JOI RNAL OF BOTANY [Vol. 46 here to denote the position of glands along the ap vides in a plane radial to the stem axis. Thus, a parent margins of the leaf, because the true morpho biseriate condition is attained. This division is logical margin, especially in upper leaves, may be shortly followed by an anticline in each cell; these recurved and fused with the lower surface of the anticlines are at right angles to the first division. leaf. Thus a quadriseriate condition (fig. 2, 24) is basic Specimens documenting fresh material or her to the subsequent development of the gland. The 4 barium specimens used are as follows, herbarium cells are soon subdivided b\ anticlinal, periclinal, abbreviations according to Lanjouw and Stafleu and oblique divisions (fig. 3, 4, 25, 26 I. Such divi i 1954) : (.. ciliosa Greene, Peirson 6449 (RSA); C. sions result in a globular multicellular condition luspida Greene, type (POM); C. mollis Gray, I fig. 5, 27). Terminal cells of this structure become l>-rris & Bacigalupi 10394 (RSA); C. multiglamlu- differentiated, by virtue of their greater size, as the losa DC. var. cephalotes (Greene) Jepson, Balls & future secreting cells of the gland. Periclinal divi Everett 18577 (RSA); ('.. oppositifoUa Greene, Rose. sions (fig. 28) increase the number of layers of 551 (RSA), Mason 4410 (RSA), Grant 796 (POM); secreting cells. The tip of the gland is then widened C. jKiuci/lora Gray, Ripley & Barneby 4690 (RSA) ; by numerous anticlines in the terminal layers (fig. C. spicata Greene. Half 9852 i POM) ; C. lenella f> i. Such anticlinal divisions result in the relatively (Nutt.) T.&.C.. Howell 1074 iRSA); C. truncata discrete appearance of these layers in the mature DC, McMurphv A-3-1908 (RSA); C. truncata gland (fig. 7, 8). 3ubap. scabreUa (Drew) Keck, Greene 3547 (POM); In the development of the stalk of the gland, cell ('.. villosa DC. Carlquist 414 I RSA i. The taxa rec layers other than protoderm participate. The deri ognized here correspond to the classification offered vation of cell lineages in stages prior to that shown I". Munz ami Kick i iii press). Infraspecific entities in fig. 6 can be followed by means of cell wall not listed were considered similar enough to other thickness. Cell walls separating protoderm from members of a species on the basis of preliminary ground meristem stain more deeply, probably on ac studies so that detailed coverage was regarded as count of more abundant accumulation of pectic unnecessary. Data on aland distribution were ob compounds. This can be seen with reasonable clar tained from study of all the Calycadenia specimens ity in fig. 14 (diagrammed in fig. 28) and more in the herbaria noted above. The writer wishes to obscurely in fig. 4 (compare with fig. 26). Such a thank the curators of those herbaria for use of their distinction is difficult to make at the stage shown in material. Acknowledgment is due the Rancho Santa fig. 6. However, stages prior to this, such as that of Ana Botanic Garden for use of cultivated plants of fig. 11, illustrate that the central portion of the stalk C. inultiglandulosa var. cephalotes. Cultivated plants is derived from ground meristem cells. Figure 6 were necessary for this study because early stages shows procambium extending into the basal portion in ontogeny occur on plants which are very difficult of the stalk of the gland. This procambium is de to find and identifv in the field, and later stages are rived from longitudinal divisions of ground mer best obtained from plants from which successive istem cells. In the mature gland, there is often a fixations can be made during a season. fairly discrete separation between layers derived ANATOMY OF THE GLANDS.—The tack-shaped from protoderm and those which are formed by glands of Calycadenia multiglandulosa var. cepha subsurface meristematic cells. The more nearly lotes were utilized because they are intermediate in isodiametric cells in the terminal portion of a ma structure between extremes which occur in the ge ture gland (fig. 7, 8; seen more clearly in C. trun nus, yet they exhibit all critical features present in cata, fig. 16) apparently represent protoderm deriv other species. The glands are goblet-shaped and atives, whereas the prosencln matous cells of the about 0.5 mm. in length. A single terminal gland basal portion of the gland represent ground meris (fig. 29) occurs on each upper leaf, and 1-6 tem derivatives (except for the stalk epidermis). glands are present laterally along the edges of the Fig. 15 shows, in C. truncata. a line of demarcation leaf. Additional glands are occasionally present which probably separates the 2 cell lineages at a above and below the midvein. The lateral glands late stage in development. Thus, no procambium (fig. 13) have somewhat narrower stalks than the in tack-shaped glands appears to be derived from terminal gland (fig. 7-8). Ontogenetic studies on protoderm. The presence of ground-meristem de ibis species showed that a distinction should be rivatives surrounded, or overarched, by proto made between terminal glands and those which oc dermal derivatives cannot be interpreted as an actu cur laterally on the leaves. These 2 types are al intrusion of ground meristem cells. Rather, elon therefore described separately. gation of the region in which ground meristem cells The first stage in the ontogeny of a terminal are present results in the conversion of this portion gland is shown in fig. 1, 23. A single protodermal into a stalk. The ground meristem below this de cell at the primordium tip becomes differentiated as velops into internal tissues of the leaf proper. an initial by virtue of increase in size. Such an The mature terminal gland of C. multiglandulosa initial is visible on very young primordia, in com var. cephalotes (fig. 7, 8) consists of a broad head parison with initials of simpler trie-homes of other supported on a somewhat narrower stalk. The Madinae (Carlquist, 19581. The single initial di terminal 2 or 3 layers may be distinguished as se- February, 1959] CARLQLIST—LEAF AND GLANDS OF CALYCADENIA 73

Fig. 9-14. -Fig. 9-13. Ontogeny of lateral glands on upper leaves of Calycadmi't multiislttndulosa var. cephalotcs. Fig. 9 from median longitudinal section of shoot apex (primordium in oblique Bection); fig. 10-13 from sagitt;il sections of primordia.—Fig. 9. One-cell stage. X430-—Fig. 10. Series nf young glands: left and center, biseriati -tagc: right, quadriseriate stage; basal portion of leaf at left. X430.—Fig. 11. Subdivision of subterminal layers. X510.—Fig. 12. Subdivision of terminal layers which will become secreting cells. X535.—Fig. 13. Mature gland, showing phloem of a vascular bundle which extends into the base of the stalk. X265.—Fig. 14. Calycadenia truncala. Sagittal section of leaf primordium adja cent to very young head. X235. 74 WIKKH \\ .l()l K\M. OF BOTANY [Vol. 46

Fig. 15-18. Sections of terminal glands on upper leaves of Calycadenia.—Fig. 15-16. C. truncata.—Fig. 15. Immature gland fr^m paradermal section. X190.—Fig. 16. Mature gland, from sagittal section of leaf. XlOO-—Fig. 17. Gland from paradermal section of leaf of C. oppositifolia. X285.—Fig. 18. Gland from paradermal section of leaf of C. pauciflora. X190- 76 AMERICAN JOURNAL OF BOTANY [Vol. 46

In some plants of C. pauciflora, glands are almost are somewhat to decidedly revolute. The revolute evenly scattered over the upper leaves, and little nature of the margin is illustrated in the anatomy distinction can be made between terminal and lat I see below) because the true margin of the leaf is eral glands. Small tack-shaped glands which are evidently joined to the lower surface. With the on transitional to capitate trichomes with biseriate set of flowering, a single upright stem is ordinarily Btalks uere observed in some species. Such transi produced. In axils of the leaves of this stem, or tional glands were always found to have multi- branches of it, short shoots, terminating in a head, seriate stalks, however. They were observed in in are produced. Leaves on these short shoots, termed volucres of C. multiglandulosa \ar. cephalotes, C. "upper leaves' here, represent more or less marked oppositifolia {Grant 796; Mason 4410), and C. vil- modifications of the basal leaves, and leaves of the losa, as weD as on upper leaves of C. villosa. upright stem are transitional to them in morphology In addition to terminal and lateral glands, simple and anatomy. The upper leaves are commonly biseriate trichomes are developed on leaves of C. shorter (0.S—1 cm.) than basal leaves and subterete in shape. I niseriate non-glandular trichomes multiglandulosa var. cephalotes (fig. 20). These are shorter and less abundant than on lower leaves, trichomes are short-lived, and are not present on or are altogether absent. I he subterete shape is mature leaves (fig- 21, '2'2i. Earlier stages of lat probably a reflection of a more complete incurving eral glands are not likely to be confused with those of the margins than in the basal leaves, as the ana of biseriate trichomes, because biseriate trichomes tomical data below suggest. develop much later. Thus, in both fig. H and 12, a primordium of a biseriate trichome may be seen in The basal leaves of C. multiglandulosa var. ceph addition to the young lateral gland. In fig. 19, the alotes I fig. 22 I show isolateral construction. At the large leaf primordium has developed a large gland margins an arc of bundles which curves toward the (base seen at extreme left I although no initials of lower surface of the leaf may be seen. Basal leaves biseriate trichomes are \et evident. Biseriate tri of C. truncata I fig. 32 I differ in possessing fibrous chomes are present on all the species of Calycadenia bundle sheaths on most of the longitudinally-ori examined. The degeneration of biseriate trichomes ented veins. Spongy parenchyma is present in the is related to the formation of a resinous coating form of a pair of marginal pectic channels in basal over the leaves. Terminal and lateral glands are leaves of C. truncata. These differences are not of persistent, however. They bear a resinous droplet great importance, however. Leaves of a single plant which may overflow the edges of the gland and may vary in respect to presence of fibers in the spread onto the leaf. The abundant resinous secre bundle sheath. The presence of pectic channels. tions of upper leaves are probably correlated with however, does distinguish leaves of C. truncata and C. ciliosa from basal leaves of other species, which the fact that these leaves are functional during the are like those described for C. multiglandulosa var. warm and dry months of late summer. cephalotes. Tack-shaped glands of Calycadenia appear to have evolved from simpler multiseriate trichomes. In upper leaves of C. multiglandulosa var. cepha Their complexity, however, is much greater than lotes (fig. 21) bundles at the margins form a promi those of other Madinae (with the possible excep nent arc. A small strand of fibers is present in the tion of Holocarpha. which will be considered in a center of this arc; the fibers are adjacent to the later study). No other glandular structures of this phloem poles of only a few bundles of the arc. As complexity have been reported previously in Com- the reconstruction in fig. 29 shows, the 2 marginal positac. although the non-vascularized glands of fiber strands are fused at the tip of the leaf. Few Catycadenia are comparable to the tack-shaped tri fibers are present in association with the midvein. chomes of Blepharizonia plumosa. The series in A consequence of the recurved arc of bundles at increasing complexity proposed earlier (Carlquist, each margin is the inverted nature of bundles on 19581 can thus be extended through Blepharizonia the lower surface of the leaf in relation to the leaf as a whole. As in the basal leaf, palisade is present to Calycadenia. Few parallels to Calycadenia glands on both surfaces. A bundle sheath extension is can be found elsewhere among angiosperms. The present on the midvein of both upper and lower "ladular structures of Droseraceae (Fenner, 1904; leaves. In basal leaves, the non-photosynthetic par Metcalfe and Chalk, 1950) are comparable in that enchyma of the central mesophyll (fig. 22) is more the stalks of such glands contain vascular tissue. abundant at the base than at the tip of the leaf. In Their function is apparently quite different from both upper and lower leaves of C. multiglandulosa that of Calycadenia glands, however. var. cephalotes, a pair of secretory canals adjacent LEAF ANATOMY.—During the year of a Calyca to the midvein was observed (fig. 29). These canals denia plant's existence, various types of leaves are are short-lived, and appear to be crushed in the produced. Following germination, a rosette of basal mature leaf. leaves is formed. These leaves are sessile, lanceo late, flat, and 2-4 cm. in length. A prominent line Stages in the ontogeny of the leaf demonstrate the of stiff unseriate non-glandular trichomes is present nature of the peculiar vascular system. In fig. 19, along the margins of these leaves, although no tack- the youngest two primordia have formed procam- shaped glands occur. The margins of these leaves bium for the midvein. Procambium for the mar- h-l.ruar>. 1959 | • if! EST—LEAF AND GLANDS OF CALYCADEN1A 77

Fig. 19-22. Transections of leaves of Calycadenia muJtiglandulosa var. cephalotes.—Fig. 19. Primordia of upper leaves; edge of apical meristem at right. X380.—Fig. 20. Half of immature upper leaf. X250.—Fig. 21. Half of mature upper leaf. X115.—Fig. 22. Half of section taken toward base of basal leaf. X90- 78 AMERICAN JOURNAL OF BOTANY [Vol. 46 ginal veins is differentiated later (fig. 19, left). Al vein and as marginal fiber groups. Marginal fiber though only a single strand of procambium is visi groups, if present, are fused at least at the tip of ble at each margin of the primordium at this stage, the leaf, although in some species they are fused for at least several marginal bundles appear to originate most of the length of the leaf (fig. 34). The term from this strand. Procambium for the vascular "pectic channels,'" used earlier by the writer (Carl- bundle which enters the terminal gland is differenti quist, 1957), refers to zones of spongy parenchvma, ated at this stage (fig. 6). Fig. 20 shows that the oriented longitudinal!) in the leaf, the intercellular marginal strand of prosenchymatous cells has en spaces of which are partly or wholly occluded by larged. At this stage, it is apparent that only the secretions of pectic compounds. The terminal por dark-staining groups of cells at the periphery of tion of the pectic channel of an upper leaf of C. this area are procambium which will differentiate truncata may be seen in fig. 15, extreme left. The into vessels. The central portion of the strand is channel is divided 1>\ tin- midvein at this level (com different, because it gives rise to fibers and paren pare with transection, fig. 31). chyma. At the stage shown in fig. 20, sieve-tube The species of Calycadenia may be summarized elements and tracheary elements have matured in as follows in respect to anatomy of upper leaves: the midvein. The procambium of bundles which C. cilosa: identical to 67. truncata. 67. hispida: interconnect the longitudinally-oriented veins is also like C. multiglandulosa var. cephalotes, except that initiated at this stage. Procambium for the in fiber strands are very prominent (touching all bun verted bundles on the lower surface of the leaf and dles except the midvein I and the midvein has a procambium extending from marginal veins to the fibrous bundle sheath. C. mollis (fig. 33) : fibrous stalks of lateral glands are formed last. Also visi bundle sheath present, in contact with lower epi ble at this stage are the 2 cell layers which will dermis: marginal fiber bundles recurved; remainder mature into palisade. Biseriate glandular and uni of mesophyU is palisade. C. oppositijolia: like C. seriate non-glandular trichomes are mature at this spicata I fig. 341, but fiber zone dorsiventrally flat stage: the former degenerate, although the latter tened. C. pauciflora: like 67. tenella (fig. 30), ex persist (fig. 21.22). They are 1-celled. In addition, cept that spongy parenchv ma is present where fibers as in all species of Calycadenia, some long, several- are indicated for C. tenella. C. spicata (fig. 34): celled uniseriate non-glandular trichomes are pres palisade forming a complete cylinder: bundle ent along the margins of basal leaves and some sheaths lacking or nearly so; fibers forming a single upper leaves. strand, around which the bundles are disposed, ex Comparison of upper leaves of 67. multiglandulosa cept at the base of the leaf, where it is divided into var. cephalotes with those of other species reveals 2 marginal fiber strands. 67. tenella (fig. 30) : differences of taxonomic interest. Moreover, they palisade extending around most of the leaf, except suggest stages in the formation of a tubular con on the abaxial side, where spongy parenchyma is struction from a condition in which only a few bun present. Bundle sheaths absent or nearly so. 67. dles follow the course of the evidently recurved mar truncata (fig. 31): palisade forming a complete gins. A beginning stage is represented by the basal cylinder around the leaf, except for the fibrous raid- leaves of all the species (fig. 22, 321. Upper leaves vein bundle sheath, which is in contact with the generally show more prominent recurved arcs of adaxial epidermis; other veins lacking bundle bundles than do basal leaves. However, upper leaves sheaths; vascular bundles forming a complete <\ Un of C. mollis I fig. 331 are much like the basal ones. der around the leaf; a few small fiber strands, not Upper leaves of C. mollis (fig. 331 seem to illus in contact with bundles, present near margins; cen trate the process clearly, for not only is the margin ter of leaf a pectic channel. C. villosa: like 67. obviously revolute in gross morphology, but many mult i glandulosa var. cephalotes, except that the bun leaves reveal a recurving in the fiber strand asso- dle sheath extends only to the adaxial epidermis. liattd with the marginal bundles, so that it has a In their vascular complexity, leaves of Calyca V-shaped appearance in transection. denia are reminiscent of those of another genus of If upper leaves of 67. mollis represent the be Madinae. Argyroxiphium (Carlquist. 1957). Leaves ginning of margin revolution and those of C. miil/i- of Argyroxiphium also possess pectic channels. The glandulosa var. cephalotes an intermediate stage, formation of three sets of bundles in Argyroxiphium upper leaves of C. truncata (fig. 311 represent the leaves has probably occurred in a manner different completion of the process. A complete cylinder of from the origin of cylindrical construction in leaves bundles is present, and these are interconnected by of C. truncata. It is of interest, however, that both transversely-oriented bundles. genera have undergone changes in foliar vasculari In respects other than vascularization, upper zation as an accompaniment to the formation of leaves of Calycadenia vary in respect to: (1) pres subterete leaves. ence and distribution of palisade: (21 presence and The advanced nature of leaf construction in C. distribution of fibers; (31 presence of bundle truncata is of interest because that species appar sheaths and bundle-sheath extensions: and (41 pres ent I \ possesses the most elaborate tack-shaped ence and distribution of pectic channels. Fibers glands in the genus. These elands are exclusively may be present as a marginal sheath for the mid- terminal; loss of lateral glands also seems a special- February, 1959] CARLQUIST—LEAF AND GLANDS OF CALYCADENIA 79

23 24 25 26 27 28

Fig. 23-34.—Fig. 23-28. Ontogeny of terminal glands on upper leaves of Calycadenia, as seen in Bagittal section of primordia; these figures represent drawings of primordia shown photographically: fig. 23 = fig. 1; (ig. 24 = fig. 2; Eg. 26 = fig. 4; fig. 27 = fig. 5; fig. 28 = fig. 14. The heavy line separates protodermal derivatives from ground meristem deriv atives: dotted lines represent probable recent divisions. Fig. 23-28, approx. X370.—Fig. 29. Reconstruction (from serial paradermal sections) of an upper leaf of C. multiglandulosa var. cephalotes. Broken lines represent veins along lower surface of leaf, unbroken lines veins of upper surface; stippled area = fibers; the two bands of vertical lines represent a pair of secretory canals. X180.—Fig. 30-34. Diagrams of transections of leaves.—Fig. 30. Upper leaf of C. tenella. XI10. —Fig. 31. Upper leaf of C. truncata. XU-—Fig- 32. Half of basal leaf of C. truncata var. scabre/la. X50.—Fig. 33. Upper leaf of C. mollis. X50.-—Fig. 34. Upper leaf of C. spicata. X70. Horizontal lines = palisade; stippled = fibers; cross- hatched = pectic channels; xylem of bundles shown in black; spongy tissue left blank in fig. 30. ;;n AMERICAN Jul K\AI. OK HOIANY [Vol. 46 ized character. Upper leaves of C. spicata and C. ment of non-vascularized glands, as in C oppositi- opposilifolia appear specialized in another direc folia, to a primitive or advanced position is difficult, tion. In these species, a cylindrical arrangement of however. Vascularized glands must have been de bundles has been achieved, but the center of the rived from non-vascularized trichomes, but non- leaf is occupied by a single fiber strand. Correla vascularized glands might in some instances have tion between glands and leaf structure in other spe resulted from reduction of a vascularized condition. cies is less clear. Calycadenia multiglandulosa var. The absence of tack-shaped glands in C. tenella like cephalotes appears to occupy an intermediate posi wise may be a reduction. tion in (he genus, because the glands are less elab CLAREMONT GRADUATE SCHOOL orate than those of C. truncata, and the leaves do RANCHO SANTA ANA BOTANIC GARDEN not have a cylindrical construction. The assign- CLAREMONT, CALIFORNIA

UTERATl'HE CITED CARLQUIST, S. 1957. Leaf anatomy and ontogeny in Argy- JOHW-KN. D. A. 1940. Plant microtechnique. McCraw Hill roxiphium and Wilkesia (Compositae). Amer. Jour. Book Co. New York. Bot. 44: 695-705. LANJOUW, J., AND F. STAFLEL". 1954. Index Herhariorum. . 1958. Structure and ontogeny of glandular tri- Part I. International Bureau of Plant Taxonomy. Ut chomes of Madinae (Compositae). Amer. Jour. Bot. recht. 45: 675-682. METCALFE, C. R., AND L. CHALK. 1950. Anatomy of the Ki NNKR, C. A. 1904. Beitriige zur Kenntnis der Anatomic dicotyledons. Clarendon Press. Oxford. Entwickelungsgeschichte und Biologie der Laubblatter Mi:\z. P. A.. \ND D. D. KECK. A California flora. Uni und Driisen einiger fnsectivoren. Flora 93: 335-434. versify of California Press. Berkeley (in press).