196 



TRAXS. ST. LOUIS ACAD. SCIENCE. 



it. Most naked chrysalides, which have the bodies appressed to 

 the object of attachment, are girded and supported by a loop 

 adroitly constructed by the larvae,* but our Lycaon chrysalis, by 

 aid of its peculiarly elongate anal pad of crochets running under 

 the end of the abdomen, is enabled to retain this position without 

 any such loop. In this it differs from all the other members of 

 its family (Nymph alid.e) which simply suspend themselves by 

 the tail, and which hang more or less directly at right angles from 

 the object of attachment, when not supported by leaves. 



Fig. 4] 



Apatura Lycaon — f, egg. magnified; g, larva, lateral view ; h, imago, underside — 

 natural size: i, j, k, I, m, the five different larval hends; », o, dorsal and lateral views of 

 larval joint— enlarged. 



The chrysalis state lasts about ten days, when the enclosed but- 

 terfly bursts the fragile shell and drags its limp self out. Clinging 

 for a time to the ruptured husk, while the compressed wings visi- 

 bly enlarge, the butterfly at last flies oft' — a perfected piece of Na- 

 ture's unrivaled handiwork. Well known in cabinets under the 

 old name of Apatura celtis Boisd., it is of a more or less intense 

 russety-gray, inclining to olivaceous and shaded with dark brown, 

 which, in certain lights, shows its relation to the European Iris by 

 a faint purple reflection. The figures (3, e, and 4, h) will stand 

 in place of more elaborate description. Aside from the genital 

 organs, the sexes are, as a rule, quite easily distinguished by the 



* This is well-known to be the rule in the Rhopalocerous families PapilionidcE, Eryci- 

 nidce, and Lycczn : die. It occurs also in some Heterocerous genera. I have bred the neat 

 little Geometrid Aridalia persimilata Grote from Ageratum, and its chrysalis mimics 

 Papilio not only in being supported by a loop, but in having ocellar tubercles. The same 

 habit obtains in the European Tineid Elachisia cinereopunctella Haw. which mines the 

 leaves of Carex (see Stainton's Nat. Hist. Tin. III., PI. 4. Fig. 1, c), and doubtless in 

 others. 



