MEMOIllS OF THE I^^ATIOXAL ACADE:\rY OF SCIENCES. 



75 



Fui. 35.— Head nf Parana chlons. 



adapted for its life in a cell, being broad, obliquely truncated, tlie small autennae being protected 



by tbe flaring sides of the head, which is very solid, with numerous rugosities and small tubercles. 



The region about the mouth is remarkable. The clypeus and labruiu are very narrow, the eye 



transversely elongated, with an impressed line in the middle. 



The eye-eollar (mr. j)-) is distinctly separated from the max- 



illiB (vix.). 



The two pieces {Ip.) at the base of the maxilla^ may pos- 

 sibly prove to be the labial palpi; if so, is the piece marked /. 



the labium! The two paraclypeal pieces or tubercles (jj.) appear 



to be the homologues of those in the Psychidic. 



The pup* of this family are very extraordinary, but it will 



be seen that they are Piq)(v incompletw, not Ptipce libene, and 



l)rove that the family should stand much above the Microptery- 



gidie rather than below tliein, so far as regards pupal characters. 

 The shape of the head of Hepudus mustelinus and the 



reduced labium, with its 

 two-jointed palpi and the 



still more atrophied maxillary palpi, are intei'esting. In H. 

 tacomce the palpi of both pairs are larger, showing that the 

 process of reduction in Hepialus is a rather late one. 



The very primitive, generalized shape of the thorax of 

 the Hepialidte is notew(U'thy. In Hepialus musteliutis the 

 collar or x^rothorax is very much reduced, while in B. tacomce 

 it is very long and generalized, as in Sthenopis and the Aus- 

 tralian Ahantiadcs argeiiteus. The mesoscutum is consider- 

 ably shorter than in R. taconuv. In the latter species the 

 metascutum is entirely divided by the large scutellum, while 

 in H. mustelinus it is only partly divided, the apex of the 

 scutellum passing a little beyond the middle of the scutum. 

 It is tlius quite evident that Sthenopis is an earlier form 

 than H. taeoma', and that the latter is more geueralized, 

 having undergone less modification than H. mustelinus. 

 The genus Hepialus occurs in Australia, and that continent appears to be the original home 



of the family. In Abantiades aryenteus the antenna^ are triiiectiiiate, and the labial palpi are very 



large ; in Hectomanes fusca the antennae are 



bipectinated, but the labial palpi are much 



reduced, being scai'cely visible, while On- 



copera intricata is remarkably modified; 



though the antennaj are simide, the eyes 



are very large, nearly meeting on the front, 



■while the three-jointed labial palpi are 



remarkably long and slender, extending 



upward, and the hind legs have a remark- 

 able broad, flattened, curved pencil of hairs. 

 It thus appears that on the Australian 



continent this interesting family, which may 



be a survival of Jurassic times and coeval 



with the marsupials, has branched out along 



several lines of specialization, tlie most 



degenerate form being Hepialus, which has 



survived also in Europe and in North 



America, especially on the Pacific Coast. On the whole, however, as we have seen, it is not so 



geueralized a group as the Micropterygidw, a group common to Europe and North America. 



Fig. 36. — Head of pupa of Megalopyge (Lagoa) 

 from Florida. 



Fig. 37.— Head of pupa of Lagoa, from Jalapa. llL-xioo; mx\ labial 

 palpi; p, paraclypeal piece ; mx., maxill.'e; mx. p. maxillary palpi. 



