37 
proportion to the hardness of their general armour : 
some have a long, projecting, serrated spear over 
the mandibles, of which others are destitute, as those 
seen in prawn compared with the shrimp. The in- 
struments for crushing their prey, however, whether 
vegetable or animal, in most of the tribe are their 
claws; which in some are tuberculated and serrated, 
and are formidable means of offence and defence, as 
in the lobster: in some, as in the shrimp and prawn, 
and especially the monoculus, they are little if at all 
applicable to these purposes. The mouths of insects 
pessess, according to their various destinations, al- 
most all the cutting, boring, and sawing instruments 
of human artisans. Yet many live their allotted 
period, with abundant supply of food, and all other 
comforts, without such machinery, imbibing liquids 
by the means of suckers. Cuvier has, accordingly, 
in his Anatomie Comparée, divided Insecta into two 
sub-classes, thus: with maxillze, gnathaptera, neuro- 
ptera, hymenoptera, coleoptera, orthoptera: without 
maxillee, hemiptera, lepidoptera, diptera, and aptera. 
These divisions include the mandibulata and hau- 
stellata of Clairville, admitting also some crustacea. 
See Kirby and Spence, vol. iv. p. 463. See also the 
minute, curious, and amusing detail of the carpentry 
of tree-hoppers and saw-flies, chap. vii. vol. iii. part i. 
of the Library of Entertaining Knowledge. The in- 
struments indeed there described are not placed in 
the mouth, but in the tail, and adapted not to pro- 
cure and secure prey, but for the purposes of ovi- 
position. The parrot-beak of the cuttle-fish is the 
D 3 
