UREDINALES OF GUATEMALA 
421 
Family: Aecidiaceae (Pucciniaceae) 
23. Ravenelia Ingae (P. Henn.) Arth. (on Mimosaceae). 
Inga edulis Mart., Chinautla, Dept. Guatemala, Feb. 12, 1916, II2, 
486',S^n Felipe, Dept. Retalhuleu, Jan. 14, 191 7, o. Hi, II2, 719. 
In studying the 1917 collection (no. 719), very large uredinio- 
spores were encountered, 37-55 m long, which were longitudinally 
striate or rugose and also reticulated. There also occurred smaller, 
echinulate urediniospores, 18-23 ix long, corresponding to those de- 
scribed in the North American Flora (7: 133). Recently the writer 
erected a new species of Inga rust {R. Whetzelii Arth., Mycol. 9: 64. 
191 7), in which the urediniospores are echinulate- verrucose and longi- 
tudinally striate, and are 30-40 ix long. As there seemed to be mix- 
tures of several forms on the Guatemalan collections, a careful re- 
examination of all material at hand was undertaken, the work being 
carried out by Dr. E. B. Mains. 
It was soon noticed that in previous descriptions and discussions, 
although pycnia were observed, there had been no discrimination 
between primary and secondary uredinia. Upon studying the primary 
and secondary forms separately, it was found that the latter had quite 
uniformly small, echinulate spores, while the former had much larger 
spores, very variable in size and sculpturing. The primary form, 
accompanied by pycnia, causes slight or no hypertrophy, while the 
secondary form, unaccompanied by pycnia, produces considerable 
hypertrophy, especially in the young caulicular parts. The type 
material for Uredo Ingae P. Henn. consists of secondary uredinia, 
while that for U. excipulata Syd., R. Ingae Arth., and R. Whetzelii 
Arth., is largely primary in each case, all now believed to represent 
variations of one species. Twenty collections have been studied, 
including all the types, from which Dr. Mains has drawn up the fol- 
lowing emended description: 
Pycnia amphigenous, numerous in crowded groups 1-3 mm. 
across, depressed hemispherical, subcuticular, dark brown, 85-160 fx, 
broad by 25-65 /x high. 
Primary uredinia amphigenous, causing no or slight hypertrophy, 
circinating about the pycnia in areas 1-6 mm. in diameter, somewhat 
tardily naked, pulverulent, dark cinnamon-brown, subepidermal, 
ruptured epidermis conspicuous; urediniospores variable in size and 
shape, obovoid, clavate, or obovoid-fusiform, 15-26 by 23-55 M» 
usually large, 32-40 /jl long or sometimes very large, 37-55 m long; 
wall golden-brown, 1.5-4 M thick, thicker at apex, 3-10 ijl, prominently 
