PHYSARUM.J PHYSAEACEjK. 41 



from Dr. Rex (L:B.M.12) marked " P. Petersii var. Farlowii, con- 

 globate form," the sporangia are in clusters of from 6 to 14 together, 

 as in the compound forms of P. p'olymorplmm. 



Hah. On dead wood. — ^Poland (Strassb. Herb) ; Africa (K. 74) ; 

 Bonin Island (K. 333); Borneo (L:B.M.12) ; Ohio (L:B.M.12) : 

 Iowa (B.M. 1012, 1015); Georgia {B.M. 853b); conglobate form, 

 Philadelphia (L:B.M.12). 



3. P. puleliripes Peck, in Bull. Buffi. Soc. F. Hist., i., p. 64 

 (1873). Plasmodium? Total height 1 to 2 mm, Sporangia 

 globose, stipitate, yellow-orange, orange-red to dark brown, 

 sometimes grey from the absence of lime, about 0-5 mm. diam. ; 

 sporangium -wall membranous, with deposits of lime usually 

 abundant, sometimes scanty. Stalk vermilion-red or red-brown, 

 0'5 to 1'5 mm. long, O'l mm. thick, somewhat narrowed upwards, 

 densely charged with red or brown lime-granules, brittle. 

 Columella conical. Oapillitium with red or brown lime-knots, 

 in other respects as in P. globuliferum. Spores violet-brown, 

 almost smooth, 6 to 8 /a diam. — Mass., Mon., p. 315. Dldymium, 

 eryihrinum Berk., in Grev., ii. (1873), p. 52 ; Mass., Mon., p. 249. 

 Didymiwm Eavenelii Berk. & Curt., ih Grev., ii. (1873), p. 53 ; 

 Physarum Eavenelii Mass., Mon., p. 281. 



Plate VII., A. — a. sporangia, x 20 ; i. capillitium and spores, x 280 ; 

 0. spore, X 600 (United States). 



A frequent species in the United States,, differing from P. globuli- 

 ferum chiefly in the colour of the lime ; and this character appears to 

 be constant. Under P. pulchripes are included Didymium erythrinum 

 Berk, and D. Eavenelii Berk. & Curt., which Bostaflnski in the 

 Appendix to his Mon., p. 8, has placed under Physarum psittacinum, 

 a species without columella and without lime-granules in the stalk. 

 Examination of the types in the Kew collection shows that the 

 sporangia of D. erythrinum (K. 1265) are immature, but those of D. 

 Eavenelii (K. 1513 and B.M. 569) possess a well-developed columella, 

 and the stalks in both types are densely charged with lime-granules. 

 . The type of P. Petersii Berk. & Ourt. in Grev., ii., p. 66 (1873) ; Eost., 

 Mon., App., p. 6 (K. 1254), belongs also to P. pulchripes. So much 

 confusion has been caused by Berkeley and Curtis in giving different 

 names to different gatherings of this species, and by Rostafinski in 

 placing P. globuliferum as a variety of P. Petersii, that Peck's name is 

 adopted as being free from ambiguity. 



Hab. On dead wood. — Massachusetts (L:B.M.13) ; Ohio (L: 

 B.M. 13) ; N. Carolina (B. M. 569, 852a). 



4. P. muriuum Lister sp. nov. Plasmodium ? Sporangia globose, 

 about 0-5 mm. diam., stalked or sessile and forming plasmo- 

 diocarps, pinkish or yellowish brown, rugose ; sporangium-wall 

 membranous, with innate clusters of brown lime-grannies. Stalk 

 erect, 0-5 mm. long or shorter, O'l mm. thick, of equal breadth 

 throughout ; pale brown, furrowed, containing dense deposits of 

 white lime-granules. Columella present in the stalked forms, 

 conical. Capillitium forming either a dense network of obtusely 

 branching hyaline threads, persistent after the dispersal of the 



