162 



ELEMENTARY ENTOMOLOGY 



FIG. 237. The nine-spotted ladybird-beetle (Cocci- 

 nella novemnotatd), adult and larva 



(After Chittendeh) 



family feed on plant-lice, scales, and other soft-bodied insects, 

 both as adults and as larvae, and may be found wherever their 

 prey becomes abundant. In general the common yellow or red, 



black-spotted species 

 feed on ... plant-lice, 

 while the smaller black 

 species, marked with 

 red or yellowish spots, 

 feed- on scales. So 

 common are the lady- 

 birds among colonies 

 of plant-lice that they 

 are frequently mis- 

 taken as- the parents 

 of the aphides, and 

 the misguided grower 

 carefully picks them off and destroys them, thinking he is elimi- 

 nating the cause of the aphid infestation, whereas he is really 

 destroying nature's most efficient agents for its alleviation. The 

 eggs are laid in little yellow masses on the leaves or bark where- 

 ever food is abundant. The larvae are commonly about one fourth 

 of an inch long, taper strongly at each 

 end, have long legs, and are often marked 

 with spiny processes. They run here and 

 there in search of food, feed voraciously 

 on any unlucky plant-lice or insects' eggs 

 which fall in their path, and, when full 

 grown, attach themselves to bark, leaves, 

 or fences by the tip of the abdomen and 

 there pupate, the cast larval skin often 

 remaining over the pupa. The beetles 

 hibernate over winter. The nine-spotted 

 ladybird (Coccinella Q-notata) is one of the larger common yellow 

 species, with nine black spots, and the little two-spotted ladybird 

 (Adalia bipunctatd) is smaller, slightly broader, and frequently 

 associated with the former species. The twice-stabbed ladybird 

 (Chilocorus bivulnerus] is black with a red spot on each wing-cover. 

 Its spiny larva is black, and, with the adult, feeds upon scale 



FIG. 238. The twice-stabbed 



ladybird-beetle (Chilocorus 



bivulnerus Muls.) and larva. 



(Enlarged) 



(After Riley) 



