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IOWA ACADEMY OF SCIENCE Vol. XXIV, 1917 
Cedar Falls, Iowa, during the dry summer and fall of 1916. 
Pycnia — Occurrence — Mostly in groups, 1 mm. to 10 mm. 
long, numerous, mostly along the midrib of the leaflet on the 
under side. Often found on the upper side, on petioles and 
stipules, near or remote from aecia. Appearance — Noticeable on 
account of the swollen areas on the leaf and the striking golden 
color of the aecia with which they are associated; generally on 
the smaller leaves covered by a canopy of larger and more vig- 
orous leaves. Color — First white water soaked areas, later, a 
dirty brown. Shape — Flasked with a globose base. Size — 
Height 118 Mu. (Aver, of 10) ; width 118 Mu. (Aver, of 10) • 
osteole 25.4 Mu. ; hymenial surface 30 Mu. ; paraphyses, length 
65 Mu., wddth 2-4 Mu.; pycnospores 2-3x4-5 (Standard 3x4). 
Twenty measured. See figure 94. 
Aecia — Numerous, scattered with pycnia which appear three 
to five days before aecia open. In mass, color a striking golden ; 
leaf appears swollen and puffed at this point or in some cases 
the entire length. More striking than the aecial stages of red 
and of white clover rust. More like the white because the symp- 
toms show better on the upper leaf surface. The first aecia ap- 
Fig. 89. — An Aecium on Red Clover. 
