72 
NATUBAL HISTOBY OF 
while they possess advantages as a subject of study 
and investigation, equal to almost any other branch 
of zoology. Such is the extent of the subject, and 
the variety of aspects in which it may be viewed, 
that minds of very different tastes and capacities 
may find congenial occupation in some one or other 
of its numerous details. The investigation of ge- 
neric and specific distinctions, which are often so 
faint and evanescent as almost to elude observation, 
accustoms the eye to habits of nice discrimination, 
— the relations which groups and families bear both 
to each other and to the different kingdoms of na- 
ture, lead to general views sufficient to exercise 
the faculties of the most gifted minds, — while the 
variety of form and structure which the species pre- 
sent, is the source of inexhaustible gratification to 
those who delight to trace the footsteps of the Cre- 
ator in his works. When to the consideration of 
their forms and habits we add the internal anatomy 
of insects, what a wide and fruitful field of enquiry is 
laid open ! The celebrated Lyonnet spent a consi- 
derable portion of his life in examining the structure 
of a single insect, and yet left much to be supplied 
by his successors to complete our knowdedge even of 
that individual species. In the body of an insect not 
exceeding an inch in length, M. Straus has enume- 
rated 306 hard pieces entering into the composition 
of the outer envelope; 494 muscles for putting these 
in motion ; 24 pair of nerves to animate them, di- 
vided into innumerable filets ; and 48 pair of tra- 
