250 Bintish UredinecF and Ustilaginecs. 



found that the sowing of the ascidiospores of ^c. piftz, both from the 

 leaves and also from the young branches, on Senecio viscosns, sylvaiici/s, 

 vernalis, jacobaa, and vulgaris^ gave rise to the uredospores of the 

 Coleosporium. In 1882, I repeated Wolff's culture on S. vulgaris with 

 the cecidiospores from the leaves with success. In 1883, the Rev. Dr. 

 Keith sent me from Forres a specimen of ^c. pini on the bark of a 

 young fir-branch, the spores from which I used for infecting two plants 

 oi S. vulgaris, but without success. Too much importance must not 

 be attached to this failure, considering the distance from which the 

 ascidiospores came. I have had, however, so many failures in in- 

 fecting S. vulgaris with the ascidiospores from A£c. pini, var. acicola, 

 that I think there must be more than one species included under this 

 name. My friend M. Max. Cornu informs me that in France he 

 has succeeded in producing Cronartium asclepiadeum by sowing the 

 ascidiospores of ALc. pini, var. acicola on Vincetoxiciim officinale. As 

 neither the Cronartium nor its host-plant occur in Britain, we must 

 conclude that the aecidiospores which M. Cornu employed belong to 

 a distinct species. 



II. HEMICOLEOSPORIUM. Winter. 



Having uredospores and teleutospores, which occur on the same host- 

 plant, 



Coleosporium sonchi. (Pers.) 



Uredospores — Sori rounded, soon pulverulent and scattered, 

 orange. Spores in short chains, rounded, oblong, or sub- 

 cylindrical, coarsely and densely verrucose, orange-yellow, 

 20-35 X 15-20/^. 



Teleutospores — Sori at first orange, then red, flat, often confluent, 

 forming crusts. Spores cylindrical or cylindrico-clavate, 

 generally four-celled, 60-70 x 15-25/x, sometimes as much 

 as 130-140/A long. 



Synonyms. 



Schrot, loc. cit., p. 368. Winter, loc. cit., p. 247. 



Uredo sonchi-arvensis. Pers., "Syn.,"p. 217. 



Uredo compransor, Schlecht. Berk., " Eng. Flor.," vol. v. 



P- 379- 



Uredo sonchi, Pers. Purton, " Midi. Flor.," vol. iii., No. 1547. 



Johnst., "Flor. Berw.," vol. ii. p. 198. Grev., "Flor. Edin.," 



p. 441. 



