14 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



2. Sori in spikelets, ovoid. 



a. Spores usually lighter colored on one side, 



5-9/"- 



* Spikelets entirely destroyed. . . U. Hordei. 

 ** Spikelets smutted only at base. . U. levis. 



b. Spores uniformly colored, 8-ii/i 



U. Crameri. 

 B. Spores echinulate or verruculose. 



1. Sorus in each spikelet, distinct. 



a. Spores usually lighter colored on one side, 



* Host Arrhenatherum avenaceum (Oat 

 Grass) U. perennans. 



** Host Avena sativa (Oats) . . .U. Avence. 



*** Host Hordewm vulgar e (Barley) 



U. nuda. 



b. Spores uniformly colored, 10-14^ 



U. Panici-glauci. 



2. Sorus involving the entire panicle 



U. Rabenhorstiana. 



3. Sori in the ovaries. 



a. Smooth and inconspicuous, 1-2 mm. 



* Spores echinulate U. spermophora. 



** Spores verruculose U. Eriocauli. 



b. Hispid and conspicuous, 4-10 mm 



U. sphcerogena. 



4. Sori in leaves (rarely on stem). 



a. Forming nodular swellings, often at nodes 



U. Crus-?alli. 



is 1 



b. Forming linear striae in the blades, 



U. striccformis. 



5. Sori breaking out on any part of host, often 



large . . . .' U. Zea?. 



II. Spores golden brown, verrucose; sori in seeds 



U. Oxalidis. 



III. Spores violet or purplish, reticulate, sori in flowers. 



1. Reticulations rather fine, 1-3/i. . . . U. anomala. 



2. Reticulations rather coarse, 2-4/t. U. utriculosa. 



