An Interesting Fungus from Friday Harbor, 

 Washington 



Sanford M. Zeller, 

 Missouri Botanical Garden, St. Louis, Mo. 



On July 4, 1917, a collecting party from the Puget Sound Biological 

 Station visited the fern cove just north of Point Caution. While collect- 

 ing maiden hair ferns (Adiantum pedattim) there was found among the 

 fern rhizomes and in the crevices under the overhanging rocky ledge a 

 quantity of sporophores of a fungus which proved to be an undescribed 

 species of Rhizopogon. This species has previously ^ been treated taxo- 

 Tiomically under the name Rhizopogon diplophloeus Zeller & Dodge, but 

 it was considered advisable to publish the collector's note here. 



Rhizopogon belongs to the family Hymenogastraceae, the genera of 

 which, for the most part, are hypogean. Species of Rhizopogon, however, 

 are either subterranean, emergent or totally superficial. 



Rhizopogon diplophloeus has puffball-like fructifications which are 

 globose to irregular, 1 — 2.5 cm. in diameter when dry, clay colored when 

 fresh, becoming darker when bruised, Verona brown to nearly black when 

 dry ; fibrils over the surface scanty, innate-appressed, black when dry and 

 leading to rhizomorphs at the base; peridium 400 — 480 fi thick, duplex, 

 the outer layer dark tawny under the microscope, about 140 — 180 /a thick, 

 composed of irregularly swollen hyphae, loosely interwoven, the inner 

 layer honey-colored, about 260 — 300 fx thick, composed of closely woven 

 hyphae; gleba from Isabella-color to brown or almost black on drying, 

 bony hard when dry ; the cavities of the gleba subglobose to somewhat 

 irregular, empty when young, filled with spores at maturity; partitions 

 between the cavities 30- — 40 ^ thick, composed of compact, subhyaline 

 hyphae, not split through the trama ; basidia clavate, 25 — 30X12 — 18 /i, 

 hyaline, 2 — 8-spored (mostly 8-spored) ; sterigniata 6 — 10 /a long; spores 

 acrogenous, dilute cream-colored under the microscope, ellipsoid, 5.3 — 7X 

 2 — 3.5 fi, smooth, often 2-guttulate. 



The present range of distribution is western Washington, one recorded 

 collection having been made by W. N. Suksdorf (811) at Bingen, Klicki- 

 tat County. 



A histological study of the development of the fructifications of differ- 

 ent species of Rhizopogon should be made to ascertain the significance 



' Zeller, S. M., and Dodge, C. W. KliizopoKoii in North America. Ann. Mo. 

 Bet. Gard. 5:1—36. pi. 1-3. 1918. 



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