200 
LIFE, IN ITS INTERMEDT ATE FORMS. 
else than the mouth, its place being caused by the inver- 
sion of the fore parts of the body, permanently in some 
species, as Rotifer, but in others, as Scandium, Furcel- 
laria, &c., transiently, the mouth being brought to the 
exterior when in action. The hammer-like pieces are the 
representatives of the upper jaws ( mandibula ), and the two 
halves of the table-like piece, against which they work, 
are the representatives of the lower jaws ( maxillce ) of 
Insects. 
The food, after having been subjected to the pounding 
and crushing action of these hammer-like jaws, passes 
off behind through a slender gullet into a capacious sto- 
mach, into which bile is poured from glands (cither a 
single pair or very numerous) which are appended to it. 
This is succeeded by an intestine, and this by a rectum, 
which terminates in an orifico behind the foot. 
It is a curious circumstance that there exists one genus 
in this Class — hence named Asplanchna — which has no 
intestine nor any posterior outlet to the stomach, the foecal 
portions of the food being regurgitated and expelled from 
the mouth. Still more remarkable is the fact, that all 
the males in the Class are entirely destitute of the diges- 
tive apparatus ; neither mouth, jaws, gullet, stomach, nor 
intestine being found, nor any vestiges of these organs, in 
any male Eotiferon. 
So far as has been observed, the sexes are separate 
throughout the class. The peculiarity just noticed is 
not the only one that distinguishes the sexes. The male 
ItoTiFERA are invariably smaller, less fully organised, and 
more short-lived than the females ; they commonly have 
scarcely any resemblance to their partners, though the 
