Mains : Heteroecism of Puccinia 



319 



consin, Indiana, southward to New Mexico and southern Cali- 

 fornia, while Berberis Fcndleri is limited in its distribution to the 

 mountains of Colorado and New Mexico. Such a difference in 

 distribution, however, would be explained if this rust is not de- 

 pendent upon its aecial stage, but is able to overwinter in the 

 uredinial stage. Mr. Bethel has made observations in Colorado 

 which indicate that such an overwintering may occur there. It is 

 probable, however, that part of the negative results obtained by 

 culturing P. montancnsis on Berberis Fcndleri can be explained 

 only by the presence of races in this rust going to different aecial 

 hosts. From present information it is impossible to foretell what 

 these hosts may be. They may be other species of Berberis or 

 Mahonia or possibly species of some closely allied family. For 

 the present the most that can be said is that Puccinia montanensis, 

 in part at least, has Berberis Fcndleri as its aecial host. 



Aecia of Puccinia montanensis 



A study to determine the identity of the aecia on Berberis Fend- 

 teri obtained from the above-described cultures resulted in finding 

 that they agree with the type of Accidium Fcndleri Tracy & Earle. 

 This type also was collected at Mancos, Colo., and Mr. Bethel 

 assures me it was collected at the same place where the material 

 used in the above cultures was obtained. The culture material 

 and the type agree in having aeciospores 18-23 by 20-30 ft. As 

 aecia on Berberis Fcndleri and the closely related Mahonia Aqui- 

 folium have been considered as belonging to Puccinia Koeleriae 

 Arth., it became necessary to make a study of the latter rust in 

 comparison with P. montanensis. 



Puccinia Koeleriae 



Puccinia Koeleriae Arth. 5 (p. 247) was based on material result- 

 ing from cultures in which aecia were produced upon Mahonia 

 Aquifolium (Pursh.) Nutt. from teliospores on Koelcria cristata. 

 An examination of the type of this species which was collected by 

 E. Bethel at Ouray, Colo., Aug. 23, 1907, shows that it has scat- 



5 Arthur, J. C. Cultures of Uredineae in 1908. Mycologia 1: 225-256. 

 1909. 



