294 GRIFFITHS: West AMERICAN FUNGI 
commonly found anywhere from the high mountains to the river 
bottoms. Its method of attack and the extent of injury done are 
very variable and apparently correlated with the vigor of the host 
which is dependent in turn upon the supply of moisture and the 
fertility of the soil. On fertile soil so situated as to receive an 
abundance of moisture in the vicinity of Cochise, plants of B. 
polystachya with scarcely a leaf or node unsmutted were but little 
if any reduced in size; but plants of the same species growing on 
sandy land near Wilcox were reduced to a small rosette of pus 
tules on the surface of the ground, not over three fourths of am 
inch in diameter, while the length of culm here averaged about 
five inches. Similar differences were observable in its method of 
attack when growing on Bouteloua aristidoides in the Santa Cruz 
valley near Tucson. 
Ustitaco Mutrorprana E. & E. anp Tittetia FuscA E. & E. 
It is strange that these two species have not found their way 
into herbaria more abundantly than they have, for there are n° 
fungi more plentiful in many portions of Montana, Wyoming, Idaho 
and Oregon than these two species. The writer has also collected 
the former in the Santa Rita Mountains in southern Arizona. 
It is also rather strange that the two species should be so com 
monly associated in the Northwest. They have been seen assocl- 
ated together at Sheridan, Wyo., Billings, Missoula and Kalispell, 
Mont., and Ontario, Ore. At both Billings and Missoula af 
abundance of plants were found affected by both species. They 
invariably, of course, select different culms for their fructification. 
The first species destroys the upper portion of the culm within the 
enlarged leaf sheath. The latter allows an apparently normal 
development of all portions of the host except the ovary which 18 
very much enlarged. The host of both species is /estuca octoflor . 
Walt. Professor F. S. Earle has compared some of my mater 
with the type of U. Mulfordiana in the herbarium of the New York 
Botanical Garden and reports that the hosts also appear to be the 
same. 
UsTILAGO ARISTIDAE Peck 
This species is very destructive to Aristida Scheideana in A 
zona, where it has been observed in several localities, but alway* 
