S96 THh: RUSTS or NOVA SCOTIA. — I'MASKIt. 



On Cirsiuin arrensc (L.) Scop., Pictoii, Truru. 



The rust on the Canada thistle is conim<»n and widely dis- 

 tribut-ed. The life historv of the fungus has been worked out 

 by Kostrup. The niycelium hibernates in the upper part of 

 the rootstock and thus the spring' shoots are infected, the 

 mycelium invading the ])]ant. The iirst generation consists 

 mostly of pycnia and uredinia, the second conies from nredinio- 

 s])ore infection and the mycelium is localized. Urediniospores 

 iire freely ])rnduc('d but no ])ycnia. 



The germ ])<>ro <tf the uj)])er cell i> placed at the apex;.lhit 

 of the lower cell is often some distance belnw the s;^])tum. 



Puccinia variabilis (iixv. 



0. Pycnia not o])served. 



1. Aecia amphigenous, mostly liypophylluus, usually on 

 fanall yellow or purple spots, solitary or in scattered small 

 groups ; peridium low, margin lacerate. Aeciospores sub- 

 ^loboi-e or ovate, 18-22 by 22-27^; contents orange, fading to 

 *^olonrless, verrucose. 



IT. Uredinia ami)hioenous, on small yellow or purple 

 fcpots, scattered, sni'all, soon naked, brown. Frediniospores 

 globose, subglobose or ovoid, 18-20 Iw 20-27m; wall brown, 

 echinulate, pores 2. 



TIT. Telia similar to th;- uredinia but dark brown. 

 Teliospores ellipsoid or oblong-cllijtsoid, 10-22 by 30-f38/A, 

 rounded at iKtth ends, slightly or not constricted at the septum; 

 wall thin, uniform, finely verrucose. dark brown; pedicel 

 hyaline, slender, deciduous. 



On Taraxacum offrcinalr Weber. Victou. I'^i-ench River. 



According to Plowright two rusts are found on Taraxacum 

 in Europe. P. Taraxaci with only the uredinial and telial 

 stages and P. rarinhiUs possessing an aecial stage as well. I 

 have found the present species so closely associated with aecia 



