389

Co.: A. H. Smith 79016 (holotype, mCii), 79203 , 79278. WASHINGroN: Pierce Co . A.H. Smith 47561.

C. olivaceopictus is one of several Dennocybes 1d th strong yellowish olive to olive colors. In general appearance i t is si milar to C. humboldt ensis but it can be separated from the latter by its smaller spores, the ferruginous to r eddish orange fibrils or fibrillose zones on the st ipe and the reddish, rather than dark inky violet, reaction of the pileus surface of fresh basidiocarps with KOH. C. tuba:r>ius Ammirati and Smith and C. hw>onensis var. oZivaceus Ammirati and Sm i th are easily separated from C. olivaceopictus by their larger spores.

CORTINARIUS THIERSII Amm i rati and Smith, sp. nov .

Fig. 2 Pileus 15- 50 mm Zatus , obtuse convexus demum plano­ convexus , umbonatus veZ subdepressus, gZaber vel sericeus veZ appresso- fibriZZosus, primo ZameZZis immatu:r>is concoZor demum ochraceo-brunneus ve Z cinruonomeo-brunneus; contextus solidus, usque 2 mm crassus, superficie piZei concoZor veZ pallidior; odor et sapor raphanini. Lamellae confel'tae vel subdissitae, ZuteoZo- bubaZinae dein paZZide ochraceo- luteae vel paZZide ochraceo- bubalinae demum fulvo- tinctae. Stipes 30- 50 mm Zongus , 4- 10 mm crassus, aequalis vel basi incrassatulus, siccus, appresso- fibrilZosus , pallide vi:r>idi - Zuteus demum paZlide luteo-bubalinus vez subochraceo­ bubaZinus, interdum pZus brunneus veZ brunneo-oZivaceus. Cortina ZuteoZa, evanescens. sporae 7. 7- 10(- 12) x 4. 7- 5.8 (- 6. 2) um, eZZipticae, verrucuZosae . HoZotypus: H. D. Thiers 1 26 33 ( SFSU) , prope Pinecrest Campground, Tuo Zumne Co ., CaZifornia, June 14, 1965.

PILEUS 15-50 mm broad, obtusely convex when young, becoming plano-convex, umbonate to shallowly depressed, i n age often irregular in outline, margin incurved becoming decurved, smoo th to sil ky or appressed fibrillose, never scaly but often lacerated or torn in age , when young more or less concolorous with the young lamellae or yellow brown (Buckthorn Brown) to olive-brown (Dresden Brown) , in age becoming ochraceous brown (Ochraceous-Tawny) to deep brown (Cinnamon Brown), in some s lightly darker on the disc or the margin more pallid. Context solid, up to 2 mm thick, more or less concolorous with the surface or slightl y pal er; 390

odor and t ast e raphanoid. LAMELLAE shallowly to deepl y notched , close t o s ubdistant, thin, some s lightly ventricose, edges even t o eroded , several tiers of 1ame11ulae, wh e n very young light yel101red 1;i th the applicat ion of KOH. SPORES 7 . 7-10(-12) x 4 . 7- 5. 8(6.2) ~m , in profile elliptic and obscurel y inequi1atera1 t o somewhat inequi­ Jateral, in face view elliptic to broadly ell iptic or slightly ovate, verrucul ose, in KOH light br01mish to light f u1 vous (Oc hraceous-Ta•my), in ~lelz er 1 s yell01

2

n . L) ®. J . ::,J :. .... ~r. • J Go5

FIGS . 1-5 Bas idiospores (x1800) . 1. Cor tinarius aurantiobasis. 2. Cor tinarius thiersii. 3. Cortinarius humboZdtensis . 4 . Cortinarius zakii. 5 . Cortinarius oZivaaeopiatus . 392

cylindrical to more or less inflat ed, 5-25 ~m ~

Caespitose to gregarious under conifers. Fruiting period: June to August.

Collections examined: CALIFORNIA: Amador Co: J.F. Ammirati 182 (SFSU); G. Breckon 413 (SFSU), 422 (SFSU); H.D. Thiers 12633 (holotype, SFS U) . IDAHO: Cus ter Co.: A.H . Smith 65655.

C. thiersii is a common species in the higher mountains of California and should be expected in the higher coniferous fares ts throughout western North America .

The large spores together with the general color­ ation of the basidiocarps distinguishes it from other species of De:rmocybe with yellOI

The large spores of C. thiersii (spores 7.7-10(-12) x 4.7-5.8(-6. 2) ~m) indicate some affinity "ith other large-spored Dermocybes, such as C. huronensis and C. ahrysoLitus Kauffman (spores 8.5-11(-12) x 5-6 .2 ~ m), that occur in the coniferous forests of eastern North America. H01;ever, more information on the distribution and eco logy of these species is needed before their relationship "ith C. thiersii can be detennined.

C. thie1'sii is named for Professor H. D. Thiers, San Franscisco State University, who f i rst collected it from California.

CORTINARIUS ZAKII Ammirati and Smith, sp. nov.

Fig. 4

Pileus 15- 45 mm Latus, e aonvexo late obtusus, wnbonatus vel subwnbonatus , siaaus, appresso- fibriZZosus , ad marginem primo oLivaaeo- brunneus deinde subfulvus demwn 1'Ufobrunneus vel valde rufobY"Unneus, disco aonaolor vel fusaior; aontextus dilute brunneus; odor et sapor plus minusve raphanini. LamelLae aonfertae, primo sordide aurantiaaae, b1'unneo-suffusae, deinde pallide brunneo­ aurantiaaae demum ferrugineo- aurantiaaae, aetate interdum maaulis rufobrunneis . Stipes 40- 75 nm longus, apiae 4- 10 mm arassus, aequalis ve L basi inarassatuLus, appresao­ fibrillosus, apiae l uteolus veL luteus, deorsum och1'aceus, brunneo- ochraceus vel pallide aurantio-och1'aceua et fibrillis brunneis vel vinaaeo-brunneis tectus . Sporae (6- )6. 5- 8 x 4- 4.5(-5) vm , ellipticae, verrucuZosae . Holotypus : J. F. Amni1'ati, Jr. 6175 (MICH) , prope Mary 's Peak, Benton Co ., Oregon , November 16, 1971.

PILEUS 15-45 mm broad, convex becoming broadly obtuse, umbonate to subumbonate, with the margin incurved to slightly decurved, dry, appressed fibrillose becoming minutely fibrillose-scal y on the margin i n age , margin at first olive-bro"n (Tawn y-Olive) or br01;ner, somet imes "ith slight ochraceous to olivaceous (Old Gold) tones, becoming light fulvous (Ochraceous -Tawny) to reddish brown (Tawny) or deep red-brown (Warm Sepia), sometimes with a