Hcmip2iccinia. 193 



thickened, bluntly conical, closely echinulate, brown, 20-35 ^ 

 12-16/X,, mixed with numerous capitate brownish paraphyses. 

 TeIciitospoi-es — Sori pulverulent, dark brown, almost black. Spores 

 consisting of two spherical cells, flattened at their point of 

 union, the lower cell often being smaller and paler. Epispore 

 uniformly thick, chestnut-brown, thickly studded with short stout 

 spines. Spores 30-45 X 17-25/x. Pedicels short, colourless. 



Synonyms. 



Puccinia priini-spinoscE, Pers. Winter in Rabh., " Krypt. Flor.," 

 vol. i. p. 193. 



Pticcinia pruni. Pers., "Syn.,"p. 226. 



Puccinia prunorum, Link. Berk., " Eng. Flor.," vol. v. p. 368. 

 Cooke, "Hdbk.," p. 507; "Micro. Fungi," 4th edit., p. 211. 

 Purton, "Midi. Flor.," vol. iii. No. 1552. 



Trichobasis rhamni. Cooke, "Hdbk.," p. 507. 



Exsiccati. 

 Baxt, 83. Cooke, i. 51 ; ii. 139. Vize, "Micro. Fungi," 128. 

 On Prtinus spinosa, domestica, Rhamnus cathartkus. 



Biology. — The teleutospores are very apt to fall asunder at the 

 septum. The frequently imperfect development of the lower cell shows 

 the relationship which exists between the present genus and Uromyces. 

 The form on Rhamnus requires to be experimentally examined. 



Puccinia argentata. (Schultz.) 



Uredospores — Sori yellowish brown, small, rounded, circinate or 

 scattered, often confluent. Spores spherical or elliptical, finely 

 echinulate, yellow, 15-20 x 14-18/x. 



Teleutospores — Sori rounded, chestnut-brown, soon pulverulent. 

 Spores ovate or clavate, rounded or attenuated above, con- 

 striction slight or absent, 25-35 X 1 2-1 7/1. Pedicels hyaline, 

 very deciduous. 



Synonyms. 



Puccinia argentata {?)c\\u\i7.). Winter in Rabh., "Krypt. Flor.," 

 vol. i. p. 194. 



yEcidium argentatum, Schultz. " Prod. Flor. Starg.," p. 454. 



O 



