SI 
SYSTEM OF NATURE. 
career, rather implies a difference in the mode of explana¬ 
tion than a change in his opinions, and T feel convinced 
that this distribution of animals, whether into four or seven 
groups, rests on so solid a foundation, that it will be a 
task of considerable difficulty to disprove its very close 
accordance with nature. 
Considering the Vertebrata as the central and normal 
division of the animal kingdom, I would suggest that the 
Cuvierian divisions of invertebrates occupy this position 
around them. — 
TNSECTA. 
k # 
E CH IN OD ERMA TA. CR US TACE A. 
VERTEBRATA. 
ZOOPHYTA. MOLLUSC A. VERMES. 
Crustacea, Echinodermata and Mollusca being the sub¬ 
normal ; Insecta, Vermes and Zoophyta the abnormal 
groups. Before assigning my reasons for supposing this 
to be the natural relative position of the primary groups 
of the animal kingdom, I must introduce a few remarks as 
to the characters to be consulted. Hitherto the whole of 
my observations have referred to animals constructed after 
the vertebra ted plan or model, and the variations from 
that model have afforded definite and tangible characters : 
now other plans come under consideration. 
G 
