THE RUSTS OF NOVA SCOTIA. FRASER. 339 



PUCCINIACHAK. 



I. Teliospores embedded in a gelatinous matrix, on 



Ooniferae Gymnosporangium. 



II. Teliospores not embedded in a gelatinous matrix, not 



on Ooniferae 



1. Teliospores one-celled Uromyces. 



2. Teliospores more than one-celled. 



A. Teliospores two^celled 



a. Aecia without peridium 



Gymnoconia. 



b. Aecia with peridium .... Puccinia. 



B. Teliospores more than two-celled 



a. Spore cells in a row 



(1) Teliospores colourless 

 Kuehneola. 



(2) Teliospores coloured 



Phragmidium. 



1}. Spore cells, three in the form of 

 a triad . Triphragmium. 



All the genera included in this synopsis are represented 

 in Nova Scotia except Gallowaya and Hyalopsora. The last 

 one will probably yet be found. 



Arthur has adopted a new system of classification of the 

 rusts. His classification is based largely on the number of 

 spore forms present. For example the genus Puccinia as now 

 commonly known is replaced by four genera, Dasyspora with 

 teliospores, Bullaria with urediniospores and teliospores, 

 Allodus with aeciospores and teliospores, and Dicaeoma with 

 all spore forms. Yet the author of the system states that "it 

 would be a wholly false impression to assume that this 

 character of the suppression of the spore forms is the only one 

 separating the genus from others of the group. It is the 

 most prominent and most easily stated, but in the most cases 

 will be found associated with other characters of accepted 



