220 MICROSCOPIC FUNGI. 



and laterally compressed. — On Salix viminalis and 8. caprcea. 

 Common. Spores perfected in February. (Plate IX. 6gs. 191, 

 192.) 



Cystopus, De Bary. 



Receptacle consisting: of thick branched threads ; conidia con- 

 catenate, at length separating ; oospores deeply seated on 

 the mycelium. 



Cystopus candidus, Lev. Crucifek, White Rust; 

 conidia equal, globose ; membrane equal, ochrapeous ; oospores 

 subglobose ; epispore yellowish-brown, with irregular obtuse 

 warts; warts solid.— On Shepherd's-purse, -Cabbages, and other 

 Crucif'erae. Summer. Very common. (Plate X. figs. 19S-200, 

 205-207.) 



Cystopus cubicus, Str. Goatsbeaud White Rust; 

 conidia unequal; terminal cell sterile, larger than the rest; 

 membrane thickener!, ochraceous, rarely yellowish ; fertile cells 

 shortly cylindrical ; membrane hyaline; oospores _ globose ; epi- 

 spore brown, verrucose ; warts hollow, round, or irregular. — On 

 Goatsbeard, Salsifv, and Scorzonera. Summer and autumn. 

 Common. (Plate X. figs. 201, 202, 210.) 



Cystopus Lepigoni, De By. Sandwort White Rust ; 

 conidia unequal; terminal cell sterile, globose; membrane 

 thickened; fertile cells subglobose or cylindrical; membrane 

 hyaline; oospores globose; epispore^ brown; tubercles minute, 

 irregular, very convex, often resembling spines. — On Spergutaria 

 rubra. Swanscombe Marshes. September. 



Cystopus spinulosus, De Bary. Thistle (White) Rust ; 

 conidia in time much elongated ; sori erumpent on both surfaces 

 of the leaves, white ; oospores globose ; epispore brown ; tubercles 

 minute, solid, very prominent, often acute and spinulose.— On 

 Thistles. Not uncommon. September. 



The residue of genera in this group contain in the majority of 

 instances imperfect forms. 



Lecythea, Lev. 



Stroma surrounded or sprinkled with elongated abortive spores. 

 Spores free, invested with their mother cell, or concatenate. 

 — Berk. Outl. t p. 334. 



* Spores free. 



