204 BULLETIN OF THE 
Famity PLATIDIIDA. 
Genus PLATIDIA Costa. 
Platidia anomoides Scaccu1. 
Platidia anomoides Dall, Bull. M. C. Z., UX. p. 104. 
Terebratula anomioides Scacchi, Philippi, Moll. Sicil., IL. p. 69, pl. xviii. fig. 9, 1844. 
Habitat. Near Morro Light, Cuba, Station 16, 292 fms.; Station 253, 92 
fms.; Barbados, Station 280, 221 fms. ; Grenada, Station 260, 291 fms.; St. 
Vincent, Station 232, 88 fms. Also San Diego, California, Orcutt; and off 
the coast of North Carolina in 16 fms. by the U. S. Fish Commission, 1885. 
Variety radiata Datt, Proc. U. S. Nat. Mus., 1885, p. 551. 
Shell radiately ribbed with small irregular ribs, apex of the dorsal valve 
not notched but even with a trace of flattened area ; hemal valve deeply 
notched ; margin with rather prominent setz lying in the grooves correspond- 
ing to the ridges ; labia as usual with short brachial membrane and fringe 
behind them; a broad smooth area of membrane in front of them ; about 
25-30 single brachial processes on each lobe turned down and curled under ; 
the point of the septum projects in front of the broad membranous area; the 
anterior labium and perhaps both of them, somewhat reinforced by chitine ; 
size the same as the typical form. 
Habitat. Station 139, off Santa Cruz, in 218 fms., bottom temperature 
51°.0; sessile on smooth Terebratula. The Californian specimens are also 
of this variety. 
This specimen was sacrificed to get at the soft parts. This is the only form 
in which the brachia are turned downward, and the only living form in which 
the hemal valve is notched in the adult state, as far as known to me. 
Famity THECIDIIDA. 
Genus THECIDIUM Sowersy. 
Thecidium mediterraneum Sowersy. 
2 Thecidium mediterraneum Sowerby, Dall, Bull. M. C. Z., IX. p. 104. 
Habitat. Station 241, 163 fms. 
The specimens being loose dorsal valves, it is possible that they may belong 
to the preceding species; but Mr. Davidson thought not. No complete speci- 
mens were found in the Blake collection. 
