THE EXTERNAL MORPHOLOGY OF THE LEPIDOPTEROUS PUPA. 45 



triangularis and says (p. 75) that, in this species, the two paraclypeal 

 pieces or tubercles appear to be the homologues of those in the 

 Psychidae. He states that they are also distinct in the Tineoids, in which 

 he includes the Tineidae, Taleporidae, Gracilariidae, Lyonetiidae (Buccu- 

 latrix), Prodoccidae, Elachistidae, Choreutidae, Psychidae, Hepialidae, 

 Cossidae, Cochlididae, and Tortricidae. In the Psychidae, the paraclypeal 

 turbercles are always present, being convex and very rugose. In de- 

 scribing the pupa of liepialus, Packard notes that, on each side (of the 

 labrum), there are, what he calls, " the paraclypeal pieces or sclerites," 

 of the homology of which he is " not quite sure, unless they are 

 identical with the tubercles seen in most Lepidoptera on each side of 

 the labrum and formerly regarded as the mandibles." Packard notes 

 the structures as being well-developed in Cochlidids and distinct in the 

 Tortricids. He further notes them as being vestigial in Enacmia, a 

 genus of uncertain position sometimes referred to the Hyponomeutidae, 

 but which Packard, by some method, appears to ally with the Litho- 

 siids. The Nolid pupa has large paraclypeal pieces. 



The eyes of nearly all lepidopterous pupae have an outer portion cut 

 off sharply from the upper and inner portion. This outer piece is 

 usually smooth and glazed, whilst the remainder of the eye is similar 

 to the rest of the pupal skin. Scudder looks on this " glazed eye," as 

 the piece is called, as the remains of an ancestral pupal eye, and says 

 that it occupies the position of the line of larval ocelli. Poulton con- 

 siders that the inner semilunar portion of the glazed eye is the true 

 eye both of larva, pupa and imago. 



Another pupal structure, apparently only noticed by Chapman, is 

 the eye-flange. Describing the pupas of the Cochlidids he writes 

 {Tram. Pint. Soc. Land.., 1894, p. 349) : " Where, in most pupae, the eye 

 abuts against the antenna, it is here rather separate, and a flat flange- 

 like margin, with sharp edge, and, in some species, marked with 

 radiating lines, surrounds the eye without quite joining the antenna." 



Chapman notes (Tram. Ent. Soc. Land., 1896, pp. 130-1) the 

 dorsal head-piece as a most persistent feature in the pupa-incompleta, 

 appearing frequently in the highest forms. He states that he at one 

 time considered it to be an anterior portion of the prothorax, but 

 concludes that there can be no doubt that it is the dorsal plate of the 

 last segment of the head, i.e., the one to which the eyes belong. It is 

 not present in the Papilionids, although found in the Hesperids, where 

 it carries the eye-covers on dehiscence. It is also to be found in a few 

 superfamilies that have obtect pupae — Lasiocampids, Cymatophorids, 

 some Geometrids,&c. — suggesting that, among these, one may find the 

 lowest obtect families and their line of origin from the Incmmpletae. 

 The Tineid stirps (the lower part of the Geometro-Eriocraniid stirps) 

 is remarkable for having a pupa which possesses an exceedingly large 

 dorsal head-plate (cephalothoracic piece), yet the structure is so 

 dwindled in the Coleophorids as to be quite evanescent, in many 

 species, in the middle line. 



The nosehorn of Chapman comprises the " ocellar tubercle " and 

 " ocellar prominence " of Scudder. It appears to be entirely a butterfly 

 structure, and to have been developed in exposed pupae in order to protect 

 the head structures, beneath which the imaginal organs are in process 

 of development. In the Papilionid pupa, the nosehorn is double, one 

 portion placed in front of each eye, and they no doubt serve for the pro- 



