CLINTON: NORTH AMERICAN USTILAGINEAE. 
% 481 
Doassansia occulta Cornu (Farl. in Trans. OttawaField Nat. Club, 2 : 127. 
1884.) 
Doassansiopsis occulta Diet., Nat. Pflanzenf., 1 1 * * : 21. 1897. 
Exsiccati: Doassansia occulta (Hoffm.), on Potamogeton Claytonii , Rab.- 
Wint.-Paz., Fungi Eur., 3801. 
Sori in ovaries, causing them to become considerably swollen, 
ovate, olive green to reddish brown ; spore balls situated in the 
endocarp, consisting of a distinct cortex within which is a single 
layer of fertile cells surrounding a central mass of parenchymatous 
cells, ellipsoidal to spherical, often irregular, 100-160 g in length; 
cortical cells polyhedral or more elongated tangentially, 8-10 y in 
length; spores adhering rather firmly, about 10-12 g in length. 
Hosts : Potamogeton Pennsylvania^ , Conn., N. Y.; Potamoge¬ 
ton sp., Ill., Ivans. 
This species seems distinct from Doassansia Martianoffiana , 
which occurs in the leaves of Potamogeton, since the two are rarely 
found associated together, and since the latter also possesses conidia. 
The germination has been described by Setchell. Literature : 48, 
160, 161. 
Doassansia occulta var. Farlowii (Cornu) Setch. 
Doassansia Farlowii Cornu, Ann. Sci. Nat., Bot, vi, 15 : 287. 1883. 
Doassansia occulta var. Farlowii Setch., Proc. Amer. Acad. Arts Sci., 26 : 
17. 1891. 
Sori and spore balls as in the species ; cortical cells smaller; spores 
chiefly oblong, about 16 g x 3-4 p. 
Hosts: Potamogeton natans , Can.; P. Penns ylvaniais , Yt. ; P. 
perfoliatus var. lanceolatus, Can.; P. pusillus , Can.; P. Vaseyi , 
Can. (type). 
Setchell kept this as a distinct variety because the spores are 
more elongated. The variety has been studied only on Potamogeton 
Vaseyi and it is possible that further study on this and the other 
supposed hosts will show that it is not so distinct as it seems to be 
from Setchell’s account. Literature: 38, 39, 160, 161. 
Doassansia Martianoffiana (Thiim.) Schrot. 
Protomyces Martianoffianus Thiim., Bull. Soc. Imp. Nat. Mosc., 53 1 : 207. 
1878. 
