496 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1925 



of eggs laid by the Lycaenidae, which are covered with an elaborate 

 and conspicuous lacework, or are much sculptured. 



The first larval stage. — The eggs hatch in three or four days. The 

 young caterpillars in the first stage are very different looking 

 creatures from the fully grown. They are of a slightly greenish 

 white with the head and legs more brownish, cylindrical, with 

 the segments slightly swollen, and the head as broad as the body, 

 obovoid, but produced at the mandibles. The hairs, which are as long 

 as three segments, are disposed, as remarked by Edwards, very much 

 as in some of the nymphalids, say Polygonia or Phyciodes. 



As described by Edwards the young larva pushes its way under the 

 large aphids, or in the case of such as are found on the plum and 

 willow among them, and immediately begins to spin for itself a 

 loose web, not close enough to conceal it from view were the aphids 

 away, h\ii sufficient to keep the aphids from walking over the body 

 and to protect it when the molt is approaching and the skin is sensi- 

 tive. The web seems to be just about the length of the larval hairs 

 from the body. The aphids may be seen running over it, and often 

 get their legs fast in the meshes and are very apt to be devoured as a 

 consequence. 



The second larval stage. — The first stage lasts about two days, when 

 the little caterpillar molts. After this first molt the body is not so 

 cylindrical, being somewhat flattened on the back and broadest in the 

 middle. As described by Scudder the body is pale mouse brown, 

 the hairs and papillae black. The hairs are nearly as long as the 

 width of the body at the extremities, slightly curved, and tapering 

 with extreme regularity to the finest possible point. They are mostly 

 arranged in a single somewhat sinuate and not entirely regular 

 transverce series a little in front of the middle of each segment. 

 Edwards describes the hairs at this stage as numerous, disposed in 

 six rows, two subdorsal, one along the middle of each side, and one 

 along the base of each side. They stand not in tufts, but in groups 

 which spring from low tuberculous swellings. The hairs along the 

 lower edge of the sides point downward and fringe the body. 



The length of the caterpillar has increased from 1.6 mm., the 

 length on hatching, to 5 mm. It still remains within the loose web 

 underneath the aphids, but its presence can now be detected by a 

 slight elevation in the otherwise uniform cylinder of aphids about 

 the alder stem. 



In the fir.st two stages the cateri)illars eat the aphids from under- 

 neath, burying their heads completely in the aphid's body. Tlie long 

 hairs on their upper surface entangle the woolly secretions of the 

 aphids so that the little caterpillars appear as if covered with flour. 



