INTRODUCTION. 3 
structure, economy, and appearance all totally different from each other. On this account, 
therefore, Clairville and Bonelli merit the greatest praise for the assiduity and perseverance 
they have shewn in the study of the Harpalide. Their labours, however, soon gave rise to the 
complaint that every species was thus becoming a genus, and that confusion instead of order 
was thus arising from their innovations. This complaint, indeed, has gradually died away 
among Entomologists ; but it has, in consequence, become a charge levelled generally against 
Entomology, by certain persons who are ignorant of the present state of the science. The 
genus Carabus of Linnzeus has, above all others, given rise to such charges ; and it must there- 
fore not a little surprise these critics to know, that after all the various mutilations which the 
genus Carabus of Bonelli has undergone, it appears in the collection of M. Dejean, whose 
catalogue, be it remembered, is very far from being extensive in extra-European insects, to con- 
tain about twice as many species as Linneeus has described of his genus Carabus. In the 13th 
edition of his Systema Nature, the latter describes only forty-three of his genus Carabus, which 
is agroupe of four modern families; whereas Baron Dejean’s collection contains cighty-three 
species of the modern genus Carabus ; and I know of about forty more. No genus can rest on 
more refined considerations than the genus Harpalus, as it at present stands; yet Dejean’s 
catalogue contains ninety-two species, of which sixty-three are European. On looking at this 
catalogue, we find that the average number of species Baron Dejean possesses in each of his 
eighty-six genera made out of the Linnean genus Carabus, is ten; that is, the same number 
which Persoon, in his last edition of the Synopsis, describes in each of his 2280 genera of plants ; 
and yet, as Decandolle has well observed, in the Théorie Elémentaire de la Botanique (p. 222), 
Persoon has in reality fewer genera, in proportion to the number of plants he knew, than 
Linneeus ; for while the former assigns ten species to each of 2280 genera, the latter naturalist 
only allows six species at an average to each of 1260 genera. So that if 1500 species of Linnean 
Carabus exist in collections,we may double the nuniber of published subgenera, and yet allow fewer 
subgenera, in proportion to the number of species we know, than Linnzeus did of genera in that 
portion of nature with which he was best acquainted, So much for the observation that every 
species is now a genus in Entomology,—an observation that has had its origin entirely in the 
inadequate idea generally prevailing as to the number of annulose species which exist. We 
every day hear of the difficulty of natural history having increased, and doubtless it is increasing 
every hour: but this is owing to the number of new species which are pouring in upon us. 
Still a great advantage has accrued to the science from the augmentation of our collections ; 
for if the study of natural affinities was formerly impossible, it has now come within 
the reach ef every person who docs not allow himself to be frightened by the multitude of 
names which necessarily crowd the pages of the best modern works on natural history. Names, 
after all, are only formidable when marshalled in an index ; and the difficulty they present to the 
young naturalist not only vanishes when it is encountered, but soon is found to be his best aid, 
in combating difficulties of infinitely greater importance, 7 
With respect to my general distribution of Clairville’s Adephaga, I have little more to say, 
than that it is asketch of natural affinities which the reader of the Hore Entomologice will find 
to illustrate certain questions there left in doubt. And if 1 have not been able to adopt that 
exposiuon of these insects which has lately been given to the public by my friends MM. Latreille 
B 2 and 
