OUTLINES OF ENTOMOLOGY. 75 



that hibernate. The only nourishment they require is an occasional 

 sip of nectar from flowers or water from a dew-drop or from the moist 

 earth. Their business in life is to seek their mates and place their eggs 

 upon the plants or other substances upon which their larvjc subsist. 

 The eggs of butterflies are usually conical and ridged or fretted on the 

 surface, and as a rule are deposited singly, while those of moths are 

 mostly spherical or circular, and deposited in clusters. 



The transformations in this order are complete, and more easily 

 observed than in most other insects. The larvcTB are all properly termed 

 caterpillars, but the smooth species are often popularly designated 

 " worms," as for example, " cut-worms," " canker-worms," " bud- 

 worms," etc. Like the parent insects, they vary greatly in form, size 

 and color. The body is usually cylindrical, composed of twelve or 

 thirteen segments, besides the head. The latter is covered by a horny 

 plate, often divided in the middle by a triangular "face," which has its 

 base at the labrum. The jaws are broad and strong, serrated or toothed 

 on the edges, the under lip (labium) is well developed, but the maxillae 

 and palpi are in most species quite rudimentary. The antennsB are 

 represented by a pair of three or four jointed tubercles, and the eyes 

 by three or four little dots or simple eyes, which probably enable them 

 to distinguish daylight from darkness. As Dr. Packard says, " this is 

 useful information from a caterpillar's stand-point, as most of them hide 

 by day and feed by night." The spineret is a small co^lnical tube on the 

 lower lip, through which a gummy substance, secreted by most cater- 

 pillars, is drawn out and becomes a line silken thread, of which these 

 insects make great use in forming their nests or cocoons, in attaching 

 themselves when molting, or suspending themselves in the air as a 

 means of escape from their enemies. 



Caterpillars, with very few exceptions, have from te7i to sixteen 

 legs — six of which, on the thoracic joints, are termed the true or tho- 

 racic legs, and are pointed and horny ; the others, which support the 

 hinder part of the body, are broad fleshy props, and are termed the 

 false legs or pro-legs; they terminate in a circle of minute hooks, by 

 which their possessor is enabled to cling to any surface upon which it 

 wishes to crawl. Some caterpillars have the surface of the body 

 smooth, while in others it is covered with hair or protected by clusters 

 of sharp branching spines, or roughened by warts and tubercles. On 

 the top of the first joint, just back of the head, there is in many spe- 

 cies a clearly defined horny plate called the cervical collar or shield, and 

 a similar plate at the hinder end forms the anal or supra-anal plate. 



