Trichia 227 



This species sometimes forms sporangia that are short-stalked 

 or entirely sessile, and crowded, appearing then like T. favoginea. 

 Such forms are distinguished from the latter by the papillose 

 character of the sporangial wall, the narrow elaters, and the spores 

 with pitted bands, more meshes to the hemisphere, and narrower 

 borders, 



3. Trichia affinis de Bary; Fuckel, Symb. Myc. 336. 1870. 

 Trichia pulchella Rex, Proc. Acad. Nat. Sc. Phila. 1893: 366. 1893. 



Plasmodium watery white (Lister). Sporangia clavate, obo- 

 void or globose, sessile, usually crowded, often seated on a mem- 

 branous hypothallus, 0.6 to 1 mm. diam., shining golden or ochra- 

 ceous yellow; mass of elaters and spores bright yellow; sporangial 

 wall membranous, pale yellow, marked with delicate irregular 

 striae, rarely reticulate in a manner resembling fan-tracing. 

 Capillitium consisting of long cylindrical elaters 4-6 n diam., with 

 conical, pointed ends, marked with four or five spiral bands, 

 smooth, rarely studded with minute, scattered spines; longitu- 

 dinal striae usually present. Spores reticulate with broad, rarely 

 narrow, pitted bands, forming a more or less complete net with 

 three to five meshes to the hemisphere, 13-15 /x diam.; border 

 0.5-1 /i wide. 



Type locality: Austria. 



Habitat: On dead wood. 



Distribution: Common throughout North America. 



Illustration: Lister, Mycetozoa ed. 3. pi. 160, figs, c, d. 



The form is intermediate between T. favoginea and T. per- 

 similis. From the former it differs by the narrower elaters, and 

 the low, broad, pitted bands on the spores, although there are 

 connecting forms between the two. From T. persimilis it differs 

 by the characters of the spores. Typical examples of T. affinis 

 or T. persimilis are not common among the many collections of 

 the two species from North America. In most of the specimens 

 the bands on the spores are broken or interrupted in greater or 

 lesser degree. This may be seen in the same colony, or even occa- 

 sionally in the same sporangium. About half of the material of 

 the two species leans nearer T. affinis and the other half towards 

 T. persimilis, in typical examples of which the bands are broken 

 up and replaced by irregular warts. The two species might well 

 be united, as there are practically no differences except in the 

 spores. T. pulchella is regarded by Lister as a phase of T. affinis. 



