ANTENNA OF LEPIDOPTERA. 45 



The Hespcriina and Papilionina are widely separated from the 

 other Lepidoptera. The anteiiiue show that they, with the other 

 Frenatse, probably branched off from the Jugatae very early. The 

 character of the chitinons surface of the clavola allies them to the 

 Frenatie and at the same time the absence of cones in all forms shows 

 that they branched off from tiie other Frenatse before the origin of 

 those organs. That the cones have been present, and have subse- 

 quently disappeared in all skippers and butterflies, is scarcely con- 

 ceivable ; that these organs have originated many times in the other 

 Frenatse is equally difficult to believe ; we must conclude, therefore, 

 that the cones originated early in the history of the Frenatie, but 

 that the Hesperiina and Pajiilionina separated from the Frenate 

 stem before that origin. It is certain also that the Hes})eriina and 

 PajMlionina separated from a stem-form conniion to the two. The 

 ventral ex])ansion producing the hook in so many members of the 

 former superfamily is probably a development brought about after 

 the separation took place. Most forms of the Hesperiina have a less 

 abrupt club than do the butterflies. The clavola thickens more 

 gradually from the proximal end, and it is often produced in a taper- 

 ing point at the apex beyond the club proper. In most other respects 

 the antennje of the two forms present many common characters. 

 The Hesperiid antenna is not so highly developed as those of the 

 other superfamily. Both in the organs they possess and in the struc- 

 ture of the whole antenna, they exhibit a lower degree of speciali- 

 zation. The aiitennte are inserted far apart, while in the Papilionina 

 they are nearer together. The recurved hook so characteristic in 

 such forms as Epar(jyreu>i titynns, Fig. 4, our most common large 

 skipper, does not occur in all forms. Megathi/inan yiuxtt, another 

 ski{)per of about the same size, but belonging to another family, 

 lacks the hook, and there is only a slight curving of the end of the 

 clavola, not more than is seen in some of the butterflies. In such 

 forms, however, the ventral expansion is a feature which distinguishes 

 them from the Papilionina. 



The Papilionina includes the Pajjilionidie, Pieridic, Lycsenidie and 

 Nym})hali(Ue. The Papilionina' rei)resents one line resulting from a 

 dichotomous division of the stem-form of the Pai)ilionina, and the 

 three other families represent the other. The members of the sub- 

 family Papilioninie have developed a type of antenna quite different 

 in some respects from that of the other forms. This confirms one 

 of tiie most important changes made in the older classifications ])y 



TRANS. AM. EXT. SOC. XXIII. MARCH. ISyb. 



