PHYTOPHAGA CHRYSOMELIDAE 



281 



\-s'*>' 



body is peculiarly shaped in conformity with the curious habit 

 of using the excrement as a covering. The larva is less elon- 

 gate than usual, and has the anus placed on the upper surface, 

 and formed so that the excrement when voided is pushed forward 

 on to the Insect ; here it is retained by means of a slimy matter, 

 and a thick coat entirely covering the creature, is ultimately 

 formed. The larva of Lema melanopa is not uncommon about 

 Cambridge, where it feeds on the leaves of growing corn. It is 

 a remarkable fact that even in one genus the species have some 

 of them this habit, but others not. The species of Crioceris 

 living on lilies C, merdigera, 

 e.g. are noted for possessing it; 

 while C. asparagi does not pro- 

 tect itself in this way, but emits 

 fluid from its mouth when dis- 

 turbed. This larva is a serious 

 nuisance in some localities to the 

 cultivators of asparagus. The 

 eggs are deposited on the stems 

 of the plant as shown in our 

 figure sometimes in great num- 

 bers. 



The perfect Insects of many 

 of the Criocerides possess a stridu- 

 lating organ. Two contiguous 

 areas at the base of the last 

 dorsal segment, where they can 

 be rubbed by the tips of the 

 elytra, are slightly elevated and 

 bear very close and fine straight 

 lines. 



ii. The CAMPTOSOMES, as we have already noticed, are distin- 

 guished by a peculiar structure of the abdomen. This character 

 appears to be connected with a very remarkable habit, viz. the 

 formation of a case to envelop the egg. The tip of the abdomen 

 is somewhat curved downwards, and, in the female, bears a 

 hollow near the extremity ; when an egg is extruded the female 

 holds it in this hollow by means of the hind legs, and 

 envelops it with a covering said to be excrementitious. When 

 the larva hatches, it remains within this case, and subse- 



B 



FIG. 143. Crioceris asparwjl. A, Eggs 

 in position on stem of asparagus ; B, 

 one egg much enlarged ; C, young 

 larva. Cambridge. 



