COLLODERMA 139 



1. Leptoderma iridescens G. Lister, Jour. Bot. 51: 1. 1913. 

 (N. Y. B. G. no. 11238, authentic material.) 



Plasmodium gray or drab (G. Lister). Sporangia scattered or 

 loosely clustered, sessile, rarely very shortly stalked, subglobose, 

 0.5 to 0.8 mm. diam., grayish purple, glossy, iridescent; sporangial 

 wall nearly hyaline above, purplish below, thickened and veined 

 with brownish granular deposits and refuse matter, often includ- 

 ing scattered, crystalline flakes of lime 2-15 n diam. Stalk short, 

 stout, dark from enclosed refuse matter, spreading below into a 

 dark hypothallus. Columella dark, convex, or absent. Capilli- 

 tium consisting of a persistent network of arching or flexuose, 

 dark purple threads, colorless at the extremities, radiating from 

 the floor of the sporangium, the pale bases often expanded and 

 tubular, and sometimes enclosing granular matter. Spores pur- 

 plish gray, spinulose, 10-11 /x diam. 



Type locality: England. 



Habitat: On dead leaves and stems. 



Distribution: Colorado. 



Illustrations: Lister, Mycetozoa ed. 3. pi. 131, figs, h, i; 

 pi. 218, figs. i-m. 



Distinguished from sessile phases of Diachea and Lampro- 

 derma, which it resembles, by the thickened, stiffened, and veined 

 lower sporangial wall and base, and the very dark capillitium. 

 The calcareous flakes are more likely to be absent or obscure. 

 The Colorado collection by Dr. E. C. Smith is practically typical. 



Suborder 11. AMAUROCHAETINEAE 



Sporangia single or combined into an aethalium, without de- 

 posits of lime} capillitium and spores dark brown or violet-brown, 

 rarely ferruginous or colorless. 



Family L COLLODERMATACEAE 



Sporangial wall with an outer gelatinous layer. 

 A single genus. 



Genus 15. COLLODERMA G. Lister, Jour. Bot. 48: 312. 

 1910. 



Sporangia usually sessile; sporangial wall consisting of two 

 layers, the outer gelatinous with superficial deposits of granular 



