(li) 

 in which the first is not longer or is shorter than the second. The segment 

 is cnived, l3ing along the eye. The inner surface (PI. LIX. f. 26. 27 ; PI. LX. 

 f. 1) is more or less regularly annulated or wrinkled, flattened, or slightly 

 convex, or somewhat concave. It is naked, except the edges, with some long 

 hair-like scales ; or it is more or less loosely sealed for the greater part. The 

 scaling at the apex of the tirst segment (PI. LIX. and LX.) is either short, or 

 long and rough, or long and quite regular, affording in several cases conspicuous 

 characters of taxonomic value — as, for instance, in the subfamily (.'liorrofanipinae, 

 where the two Neotropical genera and the cosmopolitan genus Ci'U'rio iiave 

 the scaling always rough and irregular, while all tlie allied Old World genera 

 with the exception of Pergesa and RhodaJ'ra, derivations from Celerio, have 

 it regular (PI. LIX. f. U) — 21. 26. 27). A character of the greatest importance 

 in the classification of the Hawk Moths is found at the base of the first 

 segment. That is a patch of variable size of short (and doubtless sensory) hairs, 

 which is always present in one section of the family («, PI. LIX. f. 26. 27), 

 except a few reduced forms, and equally constantly absent from the other 

 section (PI. LX. f. 1). Tiie trustworthiness of the distinctive character was 

 discovered after we had separated the Aclierontiiivtc {= Arhcrontiicni' + Spliiiigicae 

 -k-fiplnngulkae) and Amijidiciiiae from the rest of the family on other grounds. 

 This basal patcli was found in Butterflies and treated upon at some length 

 by Renter.* It is of wide occurrence in Moths. Its absence from Acherontiinae 

 and Amhulicinae has nothing to do with the reduction of the palpus, as it is 

 absent from the large palpi of Protoparce and other Sphingicae, while it is 

 found in the other subfamilies on the relatively small palpus of Onjba, Berutana, 

 and other genera. The basal patch is present in Geometrulae, Notodontidae, 

 Agaristidae, Noctuidae, Pyralidae, etc., etc., and assumes sometimes an obviously 

 distinctive form. We have not noticed it in Saturniidae and allied groups, nor 

 among Lasiontmpidae, Domhycidae, Kiiptcrotidae, and some other groups. How 

 far this organ can be made use of in the classification of tiiese families more 

 complete research must show ; but we are justified in maintaining that the 

 basal patch will prove itself elsewhere an equally good distinguishing character 

 as we find it to be in Sphingidae. 



The first segment of the palpus exhibits also on the outer side characters 

 of taxonomic value. There is a kind of transverse crest near the eye in Basiothia, 

 Aleuron, and Unzela, and the apex of the segment is strongly convex externally 

 or angulate in these genera ; the crest is also found in Gurelca and Spkhigo- 

 naepinpsis. A peculiar modification is found in one genus of AchevontUnae 

 {Megacorma) and in a great number of Choerocampinae. It is illustrated on 

 Pis. LIX. and LX. There is at the apex of the segment, ventro-laterally, a 

 space devoid of the ordinary scaling, being either quite naked or clothed with 

 a few long hair-like but flat scales. Tiie scaling around this naked space, 



• Ai-ta Siir. Sr. /■(,•««. xxii. I (ISilfi). — Hfutcr says that the ha-sal patch of Hetcrocera is never 

 ch'vatml as in I!lio|)alorera. \Vc Cml tliat it is soiuelimus raised to a oonsiiicuous riilge, for instance 

 ill PyTuVuUte. 



