REVIEWS. 305 
orakade Clark found that tne — "cid considered one of the 
mplest forms of animal life, had a s r flagellum, but that this was 
ents to procure food, which he Pt saw as it entered the sac-like 
body through a mouth situated at its base. The D of this mouth spread 
itself over the morsels which descended into a digestive vesicle in the in- 
terior of the body. The series from this point to the sponge is completed 
by a form, Salpingceca, which with the same characteristics also secretes a 
gelatinous envelope. These anatomical facts fully justified the author of 
the memoir alluded to in claiming tha discovered the true nature 
of the sponges, and they appear n nuch closer affinity be- 
e 
tween the sponges and the Uniflagellate Infusoria, and appear much 
more decisive than the coral-like characteristics described by Professor 
Heckel. 
The comparison of the aquiferous systems of sponges with the true 
stomach cavity and circulatory vessels of the coral is more than doubtful. 
sponges. It is well known that these perforations are common also in 
the star fishes and Polyzoa, and their precise import in either is as yet 
unknown. e most rational view would seem to be the opposite of 
Heeckel’s, i. e., that the pores are the mouths, and the so-called mouths the 
anal orifices, since out of these is all the refuse of the body thrown. De- 
scribing the radiating canals of Cyathiscus, the author asserts that the 
horizontal walls which divide these canals are absorbed, and the vertical 
species as an individual to possess numerous minute pores to admit food 
and rapidly enlarging canals, abutting finally in a large trunk to facilitate 
its emission. This is just the reverse of the economy of the organization 
of every individual, as such, in the animal kingdom. Individuals are uni- 
versally possessed of facilities for obtaining and swallowing food in the 
shape of large pliable mouths and stom machs, whereas the emission of the 
refuse takes place through the smaller end of the canal or through the 
mouth again 
AMER. NATURALIST, VOL. IV. 39 
