PLATE XI. 
. : Figs. 16 = Agtnopnense filicula. 
¥; Fig. 1.—Natural size. | : | 
a ' Fig, 2.—Portion of hydrocladium, magnified ; lateral view. 
“y Fig. 3.—Same; front view. ; os 
2 Fig. 4.—Corbula, closed form. . (yes 2 
Fig. 5.—Corbula, open form. | : oy F 
rn Fig. 6.—One of the costze of the open form of corbula, showing the slit-like orifice. ar a 
er its base. es N bs aay 
a Figs. 7-9.—Aglaophenia attenuata. 
, Fig. 7.—Natural size. | 
| Fig. 8.—Portion of a hydrocladium ; magnified. 
Fig, 9.—Corbula. 
