12 BULLETIN 922, U. S. DEPARTMENT OF AGRICULTURE. 



HABITS. 



The young larvae feed during the day, largely on the underside of 

 the leaves, eating small holes in them. Whether they feed from the 

 underside because it is more protected or because there are more 

 epidermal hairs for them to cling to is not known. After the third 

 molt they eat patches from the edges oi the leaves, feeding only at 

 night, and dropping to the ground when disturbed, curling themselves 

 tightly end to end. During the day they lie coiled at the base of the 

 plant, hiding under dead leaves and other debris. 



The larvae are legless but are supplied with pairs of muscular 

 fleshy tubercles on the ventrum of the segments and these are used 

 in grasping epidermal hairs, edges of leaves, etc. The young larvae 

 move about by grasping the epidermal hairs with their mouths, the 

 folds between segments, and the transverse folds. Older larvae 

 ascend petioles spirally, using the muscular abdomen as a means of 

 locomotion, and with each successive advance securing a new hold 

 with the mouth and forepart of the body. As this is repeated, the 

 larvae move around and around the stem with a spiral motion. 



When handled, the larvae will often emit a greenish saliva, which 

 appears to be for defensive purposes, and in addition may pass their 

 blackish semiliquid waste. 



The young larva molts by first coiling itself about a bunch of 

 epidermal hairs and then crawling out of the larval skin, which opens 

 in the head region, leaving the empty skin coiled around the hairs. 

 The larvae have never been observed to eat the cast skins. 



The adult, after casting off the pupal skin, which shrivels to a small 

 pellet at one end of the cocoon with the last larval skin, soon eats its' 

 way out and feeds during the summer, ragging the clover leaves and 

 sometimes eating the plants to the ground. During the day they 

 usually hide under rubbish or in cracks in the ground but have been 

 observed to feed, and many have been collected by sweeping the 

 tops of clover plants at this time. 



FEEDING EXPERIMENTS. 



Feeding experiments were conducted at La Fayette, Ind., to 

 determine the amounts of clover foliage eaten by Hypera punctata 

 at different seasons and during the larval and adult stages (Table IV) . 

 The amount of food eaten by individual larvae averages 3.09 square 

 inches of red clover foliage from 25 examples studied, and of this 

 amount 2.48 square inches, or approximately 80 per cent, is con- 

 sumed during the last instar. Comparatively small amounts of leaf 

 tissue are eaten during the first three instars — 0.019 square inch being 

 eaten during the first, 0.087 in the second, and 0.504 in the third 

 instar (Table V and fig. 8). 



