1222 THE BUTTEKFLIES OE NEW ENGLAND. 



family. It may at once be dlstingui.shed from all huttcrflies hitherto treated 

 by the four branches of the median nerviire in the fore wing, and the foliate 

 epiphysis of the fore tibiae. They are further separated from the Pierinae 

 in particular by the unsplit claws, the absence of paronychia, and by the 

 character of the inner Ijordcr of the hind wings, which is sometimes folded 

 back upon itself and encloses delicate, downy hairs, reminding one of the 

 costal fold on the fore wings of Hesperidi ; the outer border of the same 

 wings is almost imiversally crenate, besides possessing the tails already 

 mentioned. The fore wings are nearly always more or less falcate and are 

 long in proportion to their width. With few exceptions the palpi are ex- 

 cessively short, reaching only halfway up the eyes. The organ forming in 

 the males the dorsal element of the ninth abdominal segment is reduced to a 

 mere corneous strip and its office entirely supplanted Ijy the upper part of 

 the eighth segment which is prolonged backward in the form of a hook. The 

 females of a few genera are provided with a very extraordinary corneous 

 pouch or alate expansion on the under surface of the abdomen whose func- 

 tion is not yet fully known, althougli it is probably connected with oviposi- 

 tion*. The butterflies are insects of strong but irregular flight, often 

 ascending high in the air and sailing in long, sweeping curves. 



There are certain features in the Papilioninae, generally of no great 

 importance, which continually remind one of the much higher group 

 Euploeinae. They are each dominant types ; the caterpillars are stout and 

 fleshy, each often witli fleshy filaments ; the antennae are naked and have a 

 somewhat similar curve, the palpi are short, the legs long and compactly 

 scaled, the thorax and body very often similarly and rather peculiarly 

 spotted ; and even the abdominal appendages of the male Parnassius have 

 some curious elements in common with that of Anosia. 



The insects of this group are generally at least double-brooded and win- 

 ter as chrysalids. The exceptions are as usual in the group of Parnassidi 

 which are probably all single brooded, and are supposed to winter in the 

 egg. According to Gentry, hawks among birds are the special foes of the 

 butterfly. 



"M. Duponchel has published a notice relative to the genus Thais, 

 some individuals of which remained two seasons in the chrysalis state, 

 being the only instance on record of such an occurrence amongst the but- 

 terflies." (Westwood, Classif. ins., ii : 349.) Boll mentions a similar 

 case in Heraclides cresphontes, and Morris in Pai)ilio polyxenes. 



Haase (Zeitschr. f. ent., n. f. , x : 42) regards this group as of high an- 

 tiquity on account of its wide distribution coupled with the similarity of 

 neuration throughout the group. 



A very perfectly preserved fossil butterfly belonging to this group, 



*See Elwes, Proc. zool. soc. Loiul., 188G, 8-14, for the latest observations. 



