6 LAEV^ OF THE PEIONIK^. 



From the nature of their environment, protected as they are in 

 woody tissue, it naturally follows that the larvae are soft, fleshy, and 

 covered by a tough white or yellowish integument which is but slightly 

 chitinized; usually this integument is pubescent, but the amount of 

 pubescence varies with the environment. 



Legs persist in all but one subfamily of the Cerambycidse, but are 

 generally so poorly developed as to be almost f unctionless ; yet in 

 those groups of larvae which live in very soft, decayed wood, making 

 broad galleries (Lepturinae) which the body fills rather loosely, the 

 legs are best developed and may assist in locomotion, whereas some 

 genera which as a whole are borers in solid wood may have them 

 developed only as a minute spine or may lack them entirely. 



Locomotion is secured through the use of the well-developed dorsal 

 and ventral ambulatory ampullae, contracted from the anterior or 

 posterior end of the body in peristaltic succession. This constitutes 

 an efficient and rapid mode of locomotion, and is especially helpful to 

 the larva boring in solid wood when it braces itself to the sides of its 

 gallery, moving the head and thorax with a sidewise motion and 

 chiseling off the wood. The noise made in this way, which Perris 

 describes as "resembling the patter of a gentle rain," can be heard 

 in the forests on a still, warm night. 



The manner of oviposition varies. Many forms lay their eggs in 

 crevices of the bark; others will insert them deep into soft wood; 

 again, some adults will gnaw a hole through the bark, laying either a 

 single egg or a group of eggs. Few will oviposit on dry, seasoned 

 wood, but this occurs in some species, and in some cases (e. g., Pa- 

 randra) it is very probable that the adults often do not emerge, but 

 copulate and lay eggs in the wood in which they are working. 



When numerous eggs have been laid in a group it often happens 

 that the young larvae develop a cannibalistic habit and devour one 

 another. As soon as they begin to bore into the wood the individual 

 mines are kept strictly separate, and even when these mines cross 

 the larvae often bore beneath or above the older gallery. 



The immature stages of these insects vary in duration from one to 

 three or more years. By far the most usual cycle is one year, although 

 in some groups a cycle covering two or three years is normal. Moist- 

 ure and available food supply tend to increase or diminish the normal 

 time by months or years. The literature records several examples in 

 which lumber made into furniture many years has been found to 

 contain living larvae which finally emerged as imagines. 



CLASSIFICATION OF THE CERAMBYCID^ AS BASED UPON THE LARV^. 



It is a well known fact to anyone who has worked with the adults 

 of this family that the present system of classification is very inad- 

 equate. One might say that the family is overclassified, until at 



