Arthur: Cultures of Uredineae 
69 
no absolute difference between the types of P. albiperidia and P. 
tmiporula. But P. albiperidia has been cultured on Ribes, pro- 
ducing aecia that can not be distinguished from those Carex rusts 
which show urediniospores with equatorial pores only. Whether 
aeciospores grown from P. albiperidia material would reproduce 
urediniospores, when sown back on a suitable Carex, with only 
three-pored or only one-pored urediniospores, or with sori con- 
taining a mixture of the two, is yet to be demonstrated. In the 
meantime, it seems best to use the name P. albiperidia as represent- 
ing a form with aecia on Ribes, and synonymous with P. Grossu- 
lariae, while P. uniporula can be retained for such collections as 
show a preponderence of one-pored urediniospores. It is inter- 
esting to note in this connection that in Europe no Carex rust 
has yet been found agreeing with the uniporulate forms here 
discussed. 
The essential specific unity of all Carex-Ribes rusts in both 
America and Europe was the conclusion reached by Dr. H. Kle- 
bahn in 1907. Dr. Klebahn’s extended cultural work on this 
group of rusts began in 1892, and resulted in the separation of 
five species. In 1904 and 1906 he studied the behavior of Amer- 
ican material grown from teliospores transmitted by the writer. 
Taking into account both European and American material, he 
came to the conclusion® that the six described species of Carex- 
Ribes rusts were biological forms of one collective species, for 
which he suggested the name, Puccinia Ribesii-Caricis. This 
conclusion is upheld by the above study, although an earlier name 
is preferred for the species. 
2. Puccinia C.\ricis-Asteris Arth. (P. Caricis-Solidaginis 
Arth.) — Five successful cultures of this rust were secured. They 
are as follows : 
Teliospores from Carex sp., London, Ontario, sown April 10 on Aster sp., 
showing pycnia April i6, and aecia April 27. 
Teliospores from Carex sp., Lafayette, Ind., sown April ii on Aster sp., 
showing pycnia April 23, and aecia April 29. 
Teliospores from Carex retrorsa, St. Anne de Bellevue, Quebec, sown May 
14 on Aster paniculatus, showing pycnia May 22, and aecia May 27. 
Teliospores from Carex scoparia, St. Anne de Bellevue, Quebec, sown 
May 13 on Aster paniculatus, showing pycnia May 22, and aecia 
9 Klebahn, Zeits. Pflanzenkr. 3: 134. 1907. 
