PLATE XXIII. 



[Proc. Wash. Acad. Sci., Vol. II, PL XIX.] 

 (All figures drawn by aid of a camera lucida except 7<z, 1 1, 12, and 13.) 



PIG. I. Menipea erecta sp. nov. Frontal view, showing bifurcation of an inter- 

 node and main points of structure; spine (s^.), operculum (0/5.)> 

 frontal avicularia (/". a.), cecia (a;.), and mode of articulation (ar/.). 



2. Dorsal view of the same, showing the radical fibers (r. f.~) and the 

 place of their attachment upon the zoecia. 



3. Scrupocellaria scabra Van Beneden, frontal view. 



4. Dorsal view of the same, showing absence of vibracula. 



[336] (244) 



