54 INTRODUCTION. 
closely pressed to the body, that the line of separation 
is not visible. Such an error would accouut for the 
principal characteristic of these two genera. But, 
whether M. Rafinesque was deceived in this way or not, 
it is apprehended that under the circumstances, these 
genera cannot be received, although endorsed by the 
adoption of M. Fe"russac. "Whenever animals with the 
characteristics which he records, shall be discovered, it 
will be time enough to renew his names. 1 
Having thus briefly reviewed the character of these 
two authors, and criticized the works of one of them, it 
remains only to repeat, that the result of the labors of 
each, upon this branch of natural history at least, has 
1 M. Rafinesque seems to have been conscious, that he might be ob- 
noxious to the charge of publishing, as his own, discoveries that were 
already well known, and he pleads his defence, in anticipation. He says, " The 
difficulty of ascertaining sometimes, whether my discoveries are totally 
new, will not prevent me from offering those which I consider such. If a 
few shall afterwards prove otherwise, the blame, if any, must lay with those 
European compilers who give us now and then, their bulky, costly, and 
learned Cyclopedias, Dictionaries of Natural History, and Systems, without 
following the wise linnean plan of detailing nil tin- former discoveries." " In 
such a state of science I shall not be prevented from publishing my new 
species, because it may happen that one out of fifty may be previously 
noticed in some costly and inaccessible work." Having thus easily disem- 
barrassed himself of one of the chief obligations of a zoological writer, to 
wit, that i'!' fully investigating the works of his predecessors, he thus defines 
the principles which guided himself. "The principles of these tracts shall 
belong to the true linnean school of improvement. I shall follow all the im- 
provements that the worthy Linnasus would have adopted, if he had lived 
in this age; but I shall can fully avoid any deviation from the fundamental, 
rational ami everlasting rules of nomenclative, and descriptive history." 
Annuls of Nature. 
