Ce) 
subject, as well as my own particular views, for another op- 
portunity. A very few words will give a broad outline of 
the chief improvements that have been made, which is all 
that can be required here. 
It is to Latreille that we owe the division of these in- 
sects into families, which collocate into distinct groups such 
genera as possess characters in common. It was in his 
** Precis” that he first sketched this distribution which he 
has successively remodified in every subsequent work. It 
is that which he published in his ‘ Familles Naturelles du 
Regne Animal, 1825,” that I follow in the following pages, 
adapting it to the limits of our genera; but although I do 
so, it is merely temporary, until I can complete my re- 
searches upon the subject, and not because I fully agree in 
his arrangement. I have adopted the names applied by 
Dr. Leach to those families, on account of the uniformity 
of their termination. The comparision of the works of 
Latreille consequently will show his progression to the pre- 
sent comparatively natural arrangement of them: beyond 
which he has done nothing to advance this tribe since his 
establishment of a few genera in his earlier books. The 
description of species has begun to receive some attention, 
and I hope that the solid characters laid down by Jurine 
for the determination of genera, and by Vander Linden 
for species, will continue to receive the attention pre-emi- 
nently due to them. The Comte le Pelletier de St. Far- 
geau has recently described and subdivided the extensive 
genus Crabro; but the majority of the genera he has sepa- 
rated from it are removed upon much too trivial characters, 
for there is scarcely a genus which would not equally 
admit of being broken up in the same spirit of super refine- 
ment, and which would tend to generate as much confu- 
sion and perplexity as the establishment of genera upon 
