THE CYPRIS AND ITS FOSSIL ANCESTORS, 79 

triangular, with the base directed upwards. The er eaitliBlis are 
divided into teeth-like structures, and have four jointed palpi, at 
the basal joint of which is attached a branchial appendage. The 
jaws, which lie immediately behind the mandibles, consist of two 
pairs. The first pair, which is larger than the second, is divided 
into four segments, and has a large branchial plate attached, which 
is the principal breathing organ. ‘The second pair of jaws is much 
smaller than the first, to which it is attached. It is a non-articu- 
late palpus, and in the male sometimes becomes modified into a 
prehensile organ. 
There is also within the shell a pair of feet of a slender flexuous 
character, which always remain tucked up close to the body. Is 
this a modification subject to the laws of the great doctrine of 
Evolution ? or what is the reason that this little animal possesses 
' two legs, apparently never used, and, apparently, by their softness, 
incapable of being used? The post abdomen consists of two 
flattened elongated rami, which are very movable, and are strongly 
clawed at the extremity, and lie side by side mostly within the 
shell. These may probably be to assist the animal in climbing, or 
aid it in battle. ‘The eyes of the Cypris are sometimes two, but 
mostly confluent. The ovaries lie round the body, immediately 
beneath the shell, and they are so numerous and the female so 
prolific, that it is computed that one impregnation lasts an entire 
lifetime ; and, further, that the young females so produced are 
capable, for generations, of producing fresh individuals without the 
aid of the male. The male Cypris is very rarely met with. The 
copulative organs are of beautiful and peculiar structure, consisting 
of a mucous gland with a double central cylinder formed of whorls 
of radiating filaments. 
Just as the lobster sheds its shell periodically, so does the Cypris 
shed its shell or valves. 
The Cypris is not, by any means, an epicure. It will feed upon 
almost anything, and when driven to it by the forces of adversity, 
will dine upon its own brother ; but it will in the first instance fulfil 
the great object of its being, namely, eat up all decomposing animal 
matter, and then turn upon the vegetable, and, when that has 
fallen short, then—and then only—will it fall back upon a dainty 
relative. 
We said that the Cypris was cosmopolitan, and when we come 
to reflect upon his abundance in ponds of all sorts, that it is found 
pretty numerously in lakes, occasionally in high mountain tarns, 
and that it revels in rivers, estuaries, and salt marshes, we begin 
to feel indeed how justly accurate is the term, especially when we 
learn that in Lakes Superior and Huron, in America, there are 
deposits “on the grandest scale” of sands and clays enclosing 
shells of existing species. If our observation applies so pertinently 

