346 THE RUSTS OF NOVA SCOTIA. FRASEK. 



naked, pulverulent, ruptured epidermis evident. Aeciospores 

 mostly globoid, about 18-24/u; wall colourless, thick, minutely 

 verrucose. 



II. Uredinia hypophyllous, on conspicuous yellow spots, 

 usually gregarious, round, oval or irregular .3-. 6mm. across, 

 sometimes confluent, ruptured epidermis inconspicuous, soon 

 naked, somewhat pulverulent. Urediniospores globoid or 

 ellipsoid, 15-19 by 18-27/*, wall colourless, thick, evenly 

 verrucose, pores scattered; paraphyses mixed with the spores, 

 capitate, smooth, 50-80/* long, heads 19-24^ broad, wall thick, 1 

 3-5.5fi. 



III. Telia amphigenous, sometimes mostly hypophyllous, 

 scattered, often abundant and occupying most of the leaf 

 surface, roundish or irregular, often confluent, sometimes 

 elevated, orange-yellow, becoming yellowish or purplish-brown, 

 eubepidermal, teliospores prismatic, sometimes oblong, 12-15 

 by 33-44/A, rounded at both ends or truncate; wall cinnamon- 

 brown, smooth, uniformly thin or sometimes thickened above. 



Pycnia and aecia on Larix laricina (DuRoi) Koch, Pictou. 



Uredinia and telia on Scdix rostrata Richards., and other 

 Salix species, Pictou, Truro, Oakfield. 



Collections of aecia on Larix laricina were made on June 

 24, 1910, and during the following week. The aecia were 

 found to be widely distributed in the vicinity of Pictou, so 

 that almost every tree of Larix examined showed at least a few 

 infected leaves. In June, 1912, aecia were found to be very 

 abundant in one region near Pictou, the young Larix trees 

 appearing yellow at a considerable distance. It was impossible 

 to determine whether the aecia belonged to this species or to 

 M. Medusae as there is no morphological differences. It seems 

 probable, however, that these collection belong to this species 

 as cultures by the writer showed that the poplar rust in this 

 repon has aecia on Tsiiga canadensis. 



