236 Illinois State Laboratory of Natural History. 
/H, apocyni, Schw.? 
Undeveloped. ; 
On Apocynum cannabinum: McLean, June 14, 4977. 
44. Jamesianum, Peck. 
Amphigenous, on the leaves more abundant beneath. 
Spots circular, distinct, or often confluent, on the leaves some- 
what, and on the stems much swollen; ecidia subcircinate or 
irregularly crowded, short, pseudoperidium fragile, soon becom- 
ing pulverulent; spores subglobose or elliptical, epispore very 
thick, conspicuously and densely tuberculate, the tubercles 
often united in short irregular ridges, 21-36 by 24-45 », usu- 
ally about 30 by 39 »; spermagonia numerous, scattered or cen- 
trally clustered above, nearly black. 
On Asclepias Cornuti: McLean, May 26, 4799, June 1, 4886, 
June 19, 5264, June 23, 5277, July 14, 5535, July 17, 5582. 
Occurs on stems, petioles and midribs, forming swellings, 
and on both sides of the leaf, being most plentiful on the lower 
surface. It is very destructive, eating holes in leaves and 
stems. The spores are very remarkable for size, marking and 
thickness (5 ») of epispore. 
There is a different Acidium on Asclepias Corniuti, speci- 
mens of which were received from E. W. Holway, Decorah, 
Towa, labeled 4. Jamesianum. 
4 
44. fraxini, Schw. 
Hypogenous, occurring especially along the veins and upon 
the leaf-stalks. Spots definite, swollen, often purple; ecidia 
more or less densely clustered, few or many, elongate, cylindri- 
cal, tardily lacerated, but ultimately deeply split and recurved; 
spores elliptical, epispore thin, tuberculate, 21-24 by 24-32 up; 
spermagonia rather numerous, scarcely elevated, on the upper 
side of leaf, scattered over central area of the spot. 
On Fraxinus viridis: Champaign, June 8, 4915, June 10, 
4954; LaSalle, June 21, 5252; McLean, June 24, 5279, July 5, 
2427. 
