of the Gemis Doassansia , Cornu. i 5 
mentioned localities the plants of the Sagittaria were 
situated in the water and not on the bank, as often happens. 
Literature. 
Protomyces sagittariae , Farlow, Bot. Gaz., Vol. VIII, p. 276. Aug. 
1883. (Not Fuckel.) 
Doassansia hottoniae ( Rostr .), De Toni . 
In the thin, slender, much-dissected leaves of Hottonia 
palustris , the sori of this species cause neither deformity nor 
discolouration. They are light-brown in colour, ellipsoidal 
in shape, and have their long axes parallel to the long axis 
of the leaf. The tissues of the leaf are rather spongy, and 
the sori are situated just beneath the epidermis of both 
surfaces. They are circular in cross-section (120 /a to 160 \x 
in diameter), and elongated elliptical in longitudinal section 
(220 ix to 240 [x by 120 [x to 160 [x). 
The spores are polygonal, rather closely compacted, with 
rather thin walls, and pale contents, with usually a single 
large oil-drop. They are from 8 /x to 10 /x across. The 
cortical layer is much better developed than in D . epilobii 
but not as strongly as in D. sagittariae or D. alisniatis. It 
consists of a close layer of cells, which are more or less 
polygonal in tangential section and nearly square in radial 
section, being 8 /x to 12 [x by 8 /x to 10 fx. They are light- 
brown, hyaline, and show no evidence of possessing solid 
contents. The walls are slightly thickened (Fig. 67). The 
germination has not been described. 
D. hottoniae , as shown by the specimens distributed by 
Rostrup and Johanson in the various exsiccati , is a true 
Doassansia , distinguished from D. epilobii by its larger 
cortical cells. From D. alismatis and D. sagittariae it differs 
both in the shape of the sori and in habit. The cortical cells 
too are decidedly different from those of D. alismatis and to 
a less degree from those of D . sagittariae. (Cf. Figs. 67, 69, 
and 71). 
Season. From June to October, as shown by the specimens 
distributed. 
