( i) 



t 1). The fiinctionless tongue loses the trausverse auiinlatiou ; it is verj- 

 feelily rbitiuised, and vai-ies individually in length. It not rarely bears scales, 

 and is occasionally tnberculated. 



The longest tongue occurs in the tribe Sphitujicae, which tribe contains, 

 however, also species with a very short and fnnctionless tongue, and one species 

 with just a vestige of it {FJlenbechia). A short tongue is frequently found 

 among the Amhaliciiini', in which subfamily it is always shorter than the body, 

 but often strong, and in the latter case not showing any sign of reduction. 

 In the Sphingulicae the tongue is also very weak and short in most species. 

 In the other groups of Sphingidae the tongue is never excessively long aud 

 never very short, always preserving the ordinary structure aud rigiditj-. It is 

 scarcely necessary to jioint out that the fnnctionless glossa is a derivation from 

 a tongue efficient as a sucking-tube. 



As varied as the other mouth-parts are also the labial palpi, shortly 

 designated as '• jialjii " in Lepidoptera. Though this designation is, strictly 

 speaking, not correct, it is very convenient and quite precise enough, as there 

 can be no doubt that the labial pialpi, and not the vestigial maxillary ones, 

 are meant, when speaking of the ])alpi. 



The palpus, if not reduced, is large, broad in lateral asjiect, closely 

 contiguous to the head, and has a short third segment. A palpus like this 

 does not occur outside the family. However, where the palpus is reduced, the 

 general aspect is insnfficieut to recognise it as a Sphingid palpus. The most 

 slender and at the same time longest palpus is found in Tinosfoma and in the 

 S of Cressonia, in which latter genus the c? palpi are strongly divergent. A 

 very large and rounded palpus is met with in Pachylia, Eurypteryx, Frotoparce, 

 aud other genera. Reduced palpi occur abundantly among Ambulicinac and 

 Acherontiinnt', while the palpi of the other Hphingidae are mostly of medium 

 size or large, very seldom .small. The size of the palpus depends on the 

 widlii (if the segments and upon the scaling ; a broad segment covered by short 

 scales appearing much slenderer than a narrower one with long erect scaling 

 (PI. LIX. f. '..'(). 'l~). It is, as a rule, also the scaling which gives the terminal 

 portion of the palpus its particular shape. The triangularly pointed palpus and 

 the broadly rounded one, as described in systematic work, may have similar 

 segments when denuded. If one speaks of the shape of the palpus, one means 

 the palpus inclusive of the scaling as it appears in a perfect specimen. There 

 is distinct sexual dimorjihism in the palpus among AmhuUdnae, the paljms of 

 the male being often larger than that of the female. 



There are always three segments ; the third is, however, nearly always 

 very short aud concealed in the scaling of the second, projecting as a little 

 knob. In the few cases where the third segment is more distinct it is conical, 

 sometimes naked aud horn-like {Cori/tias; Xanthojxin); it is never long, slender, 

 and rod-like. In narrow palpi it is often as broad at the base as the second 

 segment is at the end. 



The first segment is the longest as a rule, but there are many exceptions 



