72 ENDOSPOREAE [PHYSARUM 



pale brown, buff or whitish, 0*1 to 0*7 mm. long, opaque 

 with enclosed refuse matter. Capillitium a network of flexuose 

 hyaline threads with numerous rounded or angular white 

 lime-knots. Spores purple-brown, minutely spinulose, 10 to 

 11 jjl diam. Didymium connaium Peck in Rep. N.Y. Mus., 

 xxvi. 74 (1874) ; Sturgis in Trans. Conn. Acad., x. 477 (1900). 

 Physarum connexum Link, Morg. Myx. Miami Valley, 92 

 (1896). P. compressum var. 8, Lister Mycetozoa, 54 (1894). 

 P. nephroideum Rost., Macbr. N. Am. Slime-Moulds, 41 

 (1899), in part. P. tropicale Macbr. I.e., 45. 



PI. 40. — c. sporangia (Iowa) ; d. capillitium and spores ; e. spore. 



This species is referred to by Dr. Sturgis (I.e.) as being one of the 

 commonest of northern New England, and is abundant also in the 

 central and western United States. In the old world it has been 

 obtained in England and Sweden. Although very nearly allied to 

 P. compressum it may be distinguished by the sporangia being more 

 symmetrical and not compressed, and by the more angular lime-knots. 

 P. tropicale Macbr. is a rather large form of the present species 

 with little lime in the iridescent sporangium-walls and in the 

 capillitium. 



Hah. On dead wood. — Bedfordshire (B.M. 2202) ; near Upsala 

 (B.M. 2203) ; Maine, U.S.A. (B.M. 1589) ; Iowa (B.M. 806) ; Mexico 

 (B.M. 2204). 



39. P. reniforme Lister. Plasmodium ? Sporangia 

 scattered or clustered, stalked or almost sessile, reniform, 

 obconic, bolster-shaped or lobed, usually compressed, - 4 to 

 0*9 mm. diam., often confluent in clusters of from three to 

 twenty or more, greyish- white ; sporangium- wall membranous, 

 with clustered deposits of lime-granules. Stalk wrinkled, 

 variable in colour, either pale yellow, yellow-brown, or 

 fuscous, usually rather slender and flexuose, 0*3 to 1 mm. 

 long, enclosing refuse matter at the base. Capillitium with 

 rshort hyaline threads connecting the numerous angular 

 lime-knots that are often united to form a pseudo-columella, 

 sometimes almost Badhamia-\ike. Spores brownish-purple, 

 either faintly or strongly spinulose, 9 to 15 /x diam. — Til- 

 madoche reniformis Mass. Mon., 336 (1892). Didymium 

 echinospora Mass. I.e., 239. Physarum nicaraguense Macbr. 

 hi BuU. Nat. Hist. Iowa, ii. 382 (1893), & N. Am. Slime- 

 Moulds, 43 ; Petch in Ann., Perad., iv. 334. P. compressum 

 Alb. & Schw., Lister Mycetozoa, 54, in part (1894). 



PI. 41. — a. sporangia (Nicaragua) ; b. capillitium and spores ; c. spore. 



This species, like the last, is nearly allied to P. compressum. It has 

 now been obtained from many parts of the world retaining the following 

 distinctive features : — the sporangia are smaller and more clustered than 

 in P. compressum, the stalks are more slender, and the capillitium 

 is often so densely charged with lime as to assume almost a Badhamia 

 character. In the type from Ceylon (K. 1406) and in Didymium 

 echinospora Mass.. also from Ceylon (K. 1407), the sporangia are reniform 



