March 1905 ] Cultures oj Uredineae in 1904. 
65 
Puccinia Stipae Arth. 
0. Spermogonia amphigenous, irregularly grouped, punctiform, 
brownish orange, subepidermal, globoid, 95-110 /* in diameter; ostiolar 
filaments free, 35-50 m long. 
I. Aecidia amphigenous, in irregular groups, on hypertrophied spots, 
brownish orange, small; peridia low, fragile and evanescent, cells abutted 
or slightly imbricated, smooth outside, tuberculate inside, thin walled; 
aecidiospores globose, 18-25 a*. in diameter, wall medium thick, 1-2 a 4 , 
brownish yellow, closely and finely verrucose, pores many, scattered, often 
conspicuous. 
On Aster multiflorus Ait., Iowa and Kansas, and also cultivated 
on A. ericoides L., and A. Novae-Angliae L. 
4. Puccinia Sorghi Schw.— Through a fortunate observa¬ 
tion in the field, June 2, 1904, upon finding aecidia on Oxcdis 
cymosa Small, the attempt was made to grow the aecidiospores on 
young com plants, which resulted in complete success. On 
June 2, aecidia-bearing leaves were suspended over potted com 
plants, under a large bell jar. On June 10 uredosori broke 
through the epidermis, and on July 10 teleutosori began to appear. 
This is taken as demonstrating the genetic connection of ^Ecidium 
Oxalidis Thuem. and Puccinia Sorghi Schw. 
A detailed account of this culture, with citation of all collec¬ 
tions of the aecidium on various species of Oxalis, known to the 
writer, has already been published in the Botanical Gazette (38:64- 
67. 1904). 
5. Puccinia Podophylli Schw. —This autoecious species 
of rust is very common in the vicinity of Lafayete, Ind. Leaves 
bearing recently opened aecidia were placed above the leaves of 
two potted plants on May 7, and both kept under bell-jars for 
three days. On May 23, one plant began to show teleutospores, 
and, on May 20, the other plant exhibited many whitish spots 
which began to burst open and display teleutospores on May 24. 
Both plants proved to be heavily infected over large areas of the 
leaves. 
The principal interest in this culture comes from the fact that 
the sowing of aecidiospores did not give rise to secondary aecidia, 
but exclusively to the characteristic teleutospores. Sydow in his 
Monog. Uredinearum (11526) states that this species has primary 
and secondary aecidia, the former being more common and form¬ 
ing extended groups, the latter coming later with the teleutospores 
and are sparsely distributed with few together in small groups. 
As many similar species of rusts have repeating aecidia, it would 
be natural to suppose that in this case the secondary generation 
arose from the aecidiospores of the first generation. The culture 
was made from a luxuriant development of the primary form; and 
from the fact that no secondary aecidia appeared, I think it can 
be safely assumed, that the so-called secondary generation arises, 
generally at least, from teleutospores, and its sparse distribution is 
due to the smaller number of sporidia which strike the leaf, or to 
