180 ON SYSTEMATIC ZOOLOGY. 
(230.) III. The third great division of M. Cuvier is 
composed of the articulated animals, of which Insrcrs 
present the typical perfection. The whole group is 
divided into four great sections: —1. The Annelides, 
or red-blooded worms; 2. The Crustacea, or crabs ; 
8. The Arachnides, or spiders; and, 4. The Insecta, or 
insects. It is in this part of his laborious work that 
our author has found it necessary to call in the assist- 
ance of M. Latreille, from whose pen the whole of the 
third and fourth volume has proceeded. We advert to 
this fact, as the circumstance has been overlooked by 
some modern writers, who have attributed to one what 
belongs to the other. 
(231.) IV. The fourth and last division of our author 
comprises what he terms the radiated animals, or 
Zoopuytes (Animalia radiata); although the term 
belongs but to a small part of those he has placed 
under this denomination. The group, in fact, com- 
prises two classes of animals, so totally different, that 
we cannot but feel surprise they should have been asso- 
ciated together. One of these groups constitute the 
Acrita, or polypes ; the other the true Radiata of this 
work. In other respects the arrangement before us is 
highly valuable, and evinces that intimate acquaintance 
with the details of these animals which laid the found- 
ation for the brilliant career of this incomparable anato- 
mist. Under these circumstances we feel compelled 
to be more particular on this class than the last. 
(232.) The class of Zoophytes is divided by M. 
Cuvier into five large groups, viz.: — 1. The Echino- 
derma, or the star-fish and sea eggs, forming the genera 
Asterias and Echinus of Linneus. 2. The Jntestina, 
intestinal worms. 3. The Acalephe, or medusas. 
4. The Polypi, or polypes. And, 5. The Infusoria, or 
animalcules. Each of these, again, are divided in the 
following manner : — 
