338 WILSON. [Vou. 1X 
the order of formation of the canals. In some individuals the 
first cavities formed are narrow rounded canals, cav., Pl. XXII, 
Fig. 88, covered in only by the dermal membrane, and which 
from the surface look like oscula. Occasionally a stage is 
found where but one of these canals exists, and that in the 
centre of the body, Fig. 90. Such a stage is interesting, be- 
cause of its essential resemblance to the young Reniera (Mar- 
shall), or Chalinula (Keller), etc., in which sponges the first 
canal to form is regularly a main central cavity which is 
ordinarily homologised with the central cavity of calcareous 
sponges and regarded as the gastrula cavity. 
Pores and oscula were developed in only a few of the sponges 
I reared, and were themselves few in number. They made 
their appearance without order, scattered about as in Esperella, 
and in other respects too their formation agreed with that of 
the same structures in the latter sponge. 
III. ApuLtT STRUCTURE AND EGG DEVELOPMENT OF 
TEDANIONE FOETIDA, N. G. 
tT: ADULT: 
It is necessary to create a new genus for this form, which, 
it would seem, however, is closely related to Tedania. The 
spiculation of the two genera separates them, though the 
occasional presence of tylotes in Tedanione coupled with the 
great similarity in the canal system and histological structure 
makes a close kinship between the two very probable. 
Diagnosts of Genus.—Spicules mostly oxeas, with micros- 
cleres of same pattern, and a very few tylotes. Flagellated 
chambers open directly into afferent and efferent canals. 
Tedantone foetida, n. sp. — Sponge amorphous with two or 
three cylindrical oscular papillae one inch high. Size, rarely 
over three inches from osculum to base. Sponge is slatebrown, 
has a fetid odor in life, and the surface is irregularly and incon- 
spicuously furrowed. Main efferent canals surrounded by large 
amount of gelatinous tissue which only occasionally comes to 
the surface. Pores rare and scattered. Subdermal cavities 
