THE RUbTS OF NOVA SCOTIA. FRASER. 351 



Aecia on Abies balasmea (L.) Mill., Pictou, July 10, 1909. 

 Uredinia and telia on Stellaria and Cerastium (Europe and 

 United States). 



The aecial stage, Peridermium elatinum (A. & S.) Kunze 

 & Schmidt, is common and widely distributed. It produces 

 the conspicuous witches' brooms so common on the balsam fir. 



Klebahn and Fischer have proved by numerous cultures 

 the connection of the aecial stage on Abies and the stages on 

 Alsine, Stellaria and Cerastium. The uredinial and Belial 

 forms are very inconspicuous, but they have been collected a 

 few times in North America, mostly in the western United 

 States. 



PUCCINIASTRUM Otth. 



Uredinia barely protruding through the epidermis; per- 

 idium present, opening by a central pore. Urediniospores 

 borne singly on pedicels with colourless walls, pores not 

 evident. 



Telia forming layers in the epidermal cells or immediately 

 beneath the epidermis. Teliospores oblong or prismatic, two 

 to four-celled by vertical or oblique walls in two planes. 



Nine species of this genus are found in North America. 

 Six are here described from Nova Scotia. Another species, 

 P. sparsum (Winter) Ed. Fisch., may occur on Arctostaphylos 

 alpina (L.) Spreng., as it has been. collected in Quebec. 



Pucciniastrum pustulatum (Pers.) Diet. 



0. Pycnia hypophyllous, abundant, inconspicuous. 



1. Aecia hypophyllous, mostly in two rows, cylindrical, 

 about 1 mm. high. Aeciospores ovoid or irregularly globoid, 

 10-20 by 16-22/x; wall colourless, finely verrucose, rather 

 thick, contents orange-yellow. 



II. Uredinia hypophyllous and frniticolous, scattered or 

 in small groups, not discolouring the leaf, small, bull ate, round, 

 dehiscent by a central pore, orange fading to pale yellow, long 

 covered by the arched epidermis; peridium hemispherical, 

 delicate, cells cuboid al, wall smooth. Urediniospores obovate 



