LINN^US. 287 



The fifth class, that in which the Insects are in- 

 cluded, comprehends 86 genera, disposed into seven 

 orders, which are founded on the number and tex- 

 ture of the wings. 



I. CoL.F.o'PTERA, or Hard-winged Insects. Insects hav- 

 ing the wings covered by two crustaceous cases. This 

 order is the most extensive, including 30 genera, and 893 

 species. It includes all the insects commonly known by 

 the name of beetles. 



II. Hemiptera, or Half-winged Insects, having the 

 shells or cases semicrustaceous, not divided by a straight 

 line as in the coleoptera, but overlapping each other at 

 the margin ; the beak curved inwards ; 12 genera, 353 

 species. The cockroach, cricket, locust, and cochineal- 

 insect, are examples. 



III. Lepidoptera, or Scaly-winged Insects, having 

 four wings, which are covered with imbricated scales ; 

 the tongue spiral and coiled up, the body hairy. In this 

 order there are only 3 genera, Papilio, Sphinx, and Pha- 

 IcBna, the butterflies and moths; but the species are 780. 



IV. Neuroptera, or Net-winged Insects, with four 

 naked, transparent, or reticulated wings ; the tail gene- 

 rally destitute of a sting. There are 7 genera, and 83 

 species, among which are the dragon-fly, the may-fly, 

 and the scorpion-fly. 



V. Hymenoptera, or Thin-winged Insects, with four 

 naked membranous wings ; some species, however, being 

 wingless. The females have the tail armed with a sting. 

 This order contains 10 genera, and 313 species, of which 

 may be mentioned as examples, the wasp, bee, ichneu- 

 mon-fly, and ant. 



VI. Diptera, or Two-winged Insects, having only 

 two wings, and being furnished with a balance or club 

 behind each wing. There are 10 genera, and 262 species, 

 among which are the common house-fly, the flesh-fly, 

 and the gnat. 



