260 INSECTS INJURIOUS TO VEGETATION. 



are said to have no feelers ; these parts being in them very 

 small, and invisible to the naked eye. 



The caterpillars of these insects differ more from each other 

 than the moths. In general they are of a cylindrical shape, 

 and are provided with sixteen legs ; there are many, however, 

 which have only ten, twelve, or fourteen legs ; and in a few 

 the legs are so very short, as hardly to be visible, so that these 

 caterpillars seem to glide along in the manner of slugs. Some 

 caterpillars are naked, and others are clothed with hairs or 

 bristles, and the hairs are either uniformly distributed, or grow 

 in tufts. Sometimes the surface of the body is even and 

 smooth ; sometimes it is covered with little warts or tubercles ; 

 or it is beset with prickles and spines, which not unfrequently 

 are compound or branched. 



Many caterpillars, previous to their transformation, enclose 

 themselves in cocoons, composed entirely of silk, or of silk 

 interwoven with hairs stripped from their own bodies, or with 

 fragments of other substances within their reach. Some go 

 into the ground, where they are transformed without the addi- 

 tional protection of a cocoon ; others change to chrysalids in 

 the interior of the stems, roots, leaves, or fruits of plants. The 

 chrysalids of moths are generally of an elongated oval shape, 

 rounded at one end, and tapering almost to a point at the 

 other ; and they are destitute of the angular elevations which 

 are found on the chrysalids of butterflies. 



These brief remarks, which are necessarily of a very general 

 nature, and comprise but a few of the principal differences ob- 

 servable in these insects, must suffice for the present occasion. 



Ijinnaeus divided the Moths into eight groups, namely, Attaci, 

 Bombyces, Noctucs, Geometrce, Tortrices, Pi/ralides, Tinecc, and 

 Alucitcs ; and these (with the exception of the Attaci, which 

 are to be divided between the Bombyces and Noctucs), have 

 been recognised as well-marked groups, and have been adopted 

 by some of the best entomologists* who succeeded him. 



* It is hardly necessary to say that among these are Denis and Schiffermaller, 

 the authors of the celebrated "Vienna Catalogue," besides Latreille, Leach, 

 Stephens, and others, whose classifications of the Moths, how much soever 

 varied, enlarged, or improved, are essentially based on the arrangement pro- 

 posed by Linnaeus. 



