72 /ournal of Mycology [Vol. 13 



Uromyces Caladii (Schu.) Farl. on Arisaema triphyllum I — 



Syracuse, 7-19-94; III Jamesville, 7-22-95. 

 Uromyces pvriformis Cke. on Acorus Calamus — Navarino, 8-15- 



95- 



Uromyces Trifolii (Hedw.) Lev. on Trifolium pratensis — Syra- 

 cuse, 9-2-91. 



Ustilag-o segetum (Bull.) Dittm. on Hordeum sp. — Otisco, y-y- 

 90. 



Ustilago Maydis (DC.) Cda. on Zea Mays — Syracuse, 8-2-95. 



NOTES FROM MYGOLOGICAL LITERATURE. XXII. 



W. A. KELLERMAN. 



Arthur, J. C. 



Clear and convincing- "Reasons for Desiring a Better Classi- 

 fication of the Uredinales" are given in the July No. of the 

 Journal of Mycology, 1906. No review or brief resume can do 

 the article justice and we content ourselves with giving a few 

 of Dr. Arthur's extracts : "There are two especially^ prominent 

 reasons for the consistent naming of the species of rusts, and 

 for other plants as well. One is to be able to designate each 

 particular kind as desired by using an authoritative name, and 

 the other is to indicate the relationship which that kind holds to 

 other kinds according to its recognized place in a natural system. 

 * * * One of the impediments at the present time to an under- 

 standing of the interrelationship of rusts lies in the lack of reason- 

 able segregation of genera.' In support of this statement one need 

 only recall the fact that the genus Puccinia as now constituted 

 contains more than half of all known species of rusts, and w^hat 

 may not be so well known, that within this category are contained 

 groups of the most diverse forms and affinities. * * * If ^ye 

 require that a genus should represent as fully as possible a group 

 of organisms giving evidence of having been derived from the 

 same ancestors, and therefore with species more closely related 

 genetically to one-anothcr than to those of any other genus, it 

 becomes necessary to explain a well known parallelism, brought 

 to our attention by Fischer of S-vitzerland. He showed that in 

 many cases the teliospores of a species having an extremely ab- 

 breviated life-cycle, e. g. Puccinia Leucanthemi, closely resemble 

 in structure those of an autoecious species, e. g., P. Aecidii- 

 Leucanthemi, in which the host of its aecia is the same or prac- 

 tically so as the host of the abbreviated species. Tranzscliel 

 has successfully applied this rule of parallelism in predicting the 

 host of the unrecognized aecia in certain heteroecious species. In 

 such cases of parallelism there can be no doubt that the forms in 

 question have truly descended from a common ancestor, but 

 dating a long way back, even to the early days when all the rusts 



