AECIAL STAGE OF ALSIKE CLOVER RUST 
467 
TABLE III. 
Stage O— Pycnia 
Host 
Spores 
High 
Wide 
Osteole 
Paraphyses 
Hymenial 
Surface 
T. repens 
1. 7x2.4 
150 
120 
17 
Numerous 
2.5x40 
35 
T. pratense— 
2-3.5 x 
3.5-5 
100 
100 
25 
Numerous to 25 
2-5 x 
25 
T. hybridum. 
2-3 x 
34-40 
4-5 
119 
119 
26 
Numerous 
9 /1 v 
QA 
The above numbers are averages of measurements and counts 
of ten pycnia, killed, sectioned serially and stained. 
Summary of the tables comparing the aecia and pycnia of 
the rust on T. hybridium with that on T. repens and T. pratense. 
1. The aeciospores on alsike clover rust are smaller than 
those of red and of white clover rust. 
2. The range of temperature for germination is much nar- 
rower than that of the other aeciospores. 
