131] LEPIDOPTEROUS LARVAE — FRACKER 131 



ments of the setae in the first larval instar. In later stages numerous 

 secondary setae are present and sometimes small cornicula (''zipfel") 

 below the spiracle, but no other form of armature. 



Family Heliconiidae 



But one species of this large tropical group ranges into the United 

 States. The larvae are all typical Nymphalidae in most particulars. 

 The characters given are drawn from Apostraphia charithonia of Flor- 

 ida but they apply also to most of the known South American forms. 



Head distinctly bilobed, bearing a long, slender scolus on each lobe ; 

 front not reaching half way to top of head ; color green with ocelli 

 located on a black spot and another pair of black spots on the epicra- 

 nium near the union of the arms of the epicranial suture. 



Prothorax smaller than head, bearing a dorsal shield; shield with 

 one large seta but no scoli; mesothorax and metathorax each bearing 

 a subdorsal pair of scoli and one on each side slightly above the spiracu- 

 lar level ; no subspiraeular scoli present on thorax, but several verrucae 

 located at the base of each leg. Abdomen with three scoli present on 

 each side on each segment, one subdorsal, one supraspiracular, and one 

 subspiraeular; no scoli on dorsomeson; small chalaza or scolus present 

 on abdominal segments 1, 2, 7, and 8, in line with prolegs in the position 

 of the Pi group and another very small one in the position of sigma; 

 scoli all very long and slender, nearly as long as body is wide ; secondary 

 setae minute or absent above level of prolegs, small on ventral surface. 

 Prolegs all present and well developed ; crochets biordinal or triordinal, 

 arranged in a mesoseries. 



The above description applies equally well in almost every particu- 

 lar to Agraulis of the Nymphalidae, but in that genus the scoli are not 

 quite so long and slender. The shape of the head offers the most con- 

 venient means of differentiating the two genera, altho the difference 

 is hard to describe. In the Heliconiidae the head scoli are located back 

 of the plane of the front and are not borne on conical projections of 

 the head. The scoli of Agraulis are borne on prominent conical pro- 

 jections which gradually merge into the scoli and which extend ceph- 

 alodorsad so that the bases of the scoli are somewhat cephalad of the 

 plane of the front. 



Family Agapetidae 



The larvae of the satyrs differ from other Nymphaloidea in several 

 particulars and their external characters do not indicate a very close 

 relationship. All their relatives except Anaea and Hypatus have an 

 external armature consisting of scoli or fleshy filaments. On the other 

 hand none but the Agapetidae have a bifurcate suranal plate. 



