138 Mycetozoa of North America 



in all respects with the type material of R. Carestiana. It is pos- 

 sible that Macbride & Martin intended to refer to Harkness 

 no. 23/29, from California, which is type material of Didymium 

 granuliferum Phill. 



3. Lepidoderma Chailletii Rost. Mon. 189. 1874. 



Plasmodium dirty white (Lister). Sporangia loosely clus- 

 tered or crowded, globose or hemispherical, 0.5 to 1 mm. diam., 

 short-stalked, sessile, or forming plasmodiocarps, gray or drab, 

 with close-set crystalline scales of lime; sporangial wall somewhat 

 cartilaginous, yellow or pale purplish. Hypothallus orange or 

 brown, sprinkled with calcareous scales, of spongy texture within. 

 Stalk short, brown, rising from the hypothallus. Columella pale 

 or dark brown, rarely orange, clavate, hemispherical, or absent, of 

 a spongy texture and containing lime-nodules. Capillitium of 

 slender purplish threads, branched and anastomosing. Spores 

 purplish gray or purplish brown, spinulose, sometimes paler on 

 one side, 10-14 ix diam. 



Type locality: Bohemia. 



Habitat: On dead leaves, stems, and twigs. 



Distribution: California, *Washington. 



Illustration: Lister, Mycetozoa ed. 3. pi. 116. 



This species is distinguished from L. Carestianum by the more 

 frequent habit of forming distinct sporangia, often with stalks 

 arising from a hypothallus, the paler sporangial walls, and the 

 more slender and smoother threads of the capillitium. Numerous 

 intermediate forms are said to occur in Europe, where it and the 

 allied forms are more abundant, and may be expected here with 

 more plentiful collections. The spores in the California collection 

 are normal in size, although more brownish than in other speci- 

 mens from Europe. The columella is lacking. 



Genus 14. LEPTODERMA G. Lister, Jour. Bot. 51: 1. 

 1913. 



Sporangia subglobose, the membranous walls thickened to- 

 wards the base with dark granular deposits, among which small, 

 calcareous scales are often embedded. Capillitium a dense net- 

 work of blackish threads. Spores purplish gray. 



A SINGLE species. 



