CHITONID&. 239 
CHITONIDZ. 
Before I enter on this family, I beg to state, that a more 
extended experience of the Mollusca has compelled me to 
relieve myself, in part, of the assistance of conchological attri- 
butes, as I have found them singularly defective and fallacious 
in reference to the existing constitutions of divisions, families 
and genera. I therefore, as regards the past, and henceforth, 
shall only consider the shell-coverings of the Mollusca as good 
and useful aids, in strict subservience to the malacology of the 
animal, and as consequential specialties emanating from the 
vital organs; and that the meaning of whatever appellation 
may be attached to a division, family or genus, has with me 
no reference to the testaceology: for mstance, speaking of the 
Muricide, or its synonym, the Canalifera, the shell is not in 
question, except as a corroborating incident, but the animalia 
canalifera, whose mantles form canals; and in like manner, 
in mentioning the Holostomata, the entire periphery of the 
aperture is not primarily intended, but, that the mantle lining 
it is entire. 
The use of the word ‘shell,’ instead of ‘animal,’ in the con- 
_ struction of the subordinate divisions of a class, has doubtless 
arisen from the ignorance of naturalists of the inhabitants ; 
but as this cause is in a great measure removed, it is time 
to abandon a system founded on fallacious bases, and have 
recourse to nature’s imperishable land-marks. 
In these observations, I do not mean to say that conchology 
is without its use: to paleontologists, collections of shells are 
the only resources to denote that their fossils present similari- 
ties to many existing forms; but how infinitely more valuable 
is an account of an existing animal, to inform them of the real 
character of the relics of former epochs! Beyond the re- 
stricted pomts, conchology is totally unworthy to be the suc- 
cedaneum of the attributes of nature, and the true worshipers 
of the great book will rejoice at the decadence of a usurpation 
to its just limits. 
