GRAND DIVISIONS. g. 
Linneus left them, or nearly so. Insecta is di- 
vided into three classes, to which is pretixed a 
class taken from Vermes. ‘They are Annelida, 
Crustacea, Arachnida, and Insecta. ‘The re- 
mainder of the class Vermes is divided into Mol- 
fusca, Echinoderma, Intestina, Acalepha, Polypi 
and Infusoria. ‘The subdivisions are adopted in 
this text-book. 
GRAND DIVISIONS. 
Tur suBJECTS OF ZOOLOGY ARE DISTRIBUTED 
INTO FOUR GRAND DIVISIONS 3 BECAUSE ANIMALS 
APPEAR TO HAVE BEEN ORGANIZED UPON FOUB 
GENERAL PLANS, 
[. RADIATED ANIMALS or ZOOPHYTES. 
In this division the sentient principle is lodged. 
in, or, in some unknown manner, attached to, @ 
medullary globule, spheroid or ring, with radiat- 
ing branches. 
Animals of this class are but little more com- 
plicated in their structure than plants. No dis- 
tinct system of nerves nor any ergans of sense, 
have been discovered. Feint vestiges of circula- 
tion are with difficulty perceived. Their respi- 
ratory organs are mostly on the surface of the 
body. Some receive their food through a mouth, 
others through pores. 
Some animals of this division may be cut across, 
and both parts will live. ‘This is explained by 
supposing the animal to consist of a celumn or 
pile of distinct animals, and that the transverse cut- 
ting produces a mere separation of a column of 
individuals into several shorter columns, 
