THE SPHINGO-MICROPTERYGIDES. 119 



in some families, appendages that project beyond the 4th abdominal 

 segment. The Pterophorid pupa is a true Micro in dehiscence, has 

 the 4th abdominal segment free in both sexes (and the 7th also in the 

 male), the dorsal headpiece is evanescent, and it has lost the maxillary 

 palpi. As Chapman concludes that "it is impossible for one of these 

 forms to be derived from the other," we consider ourselves quite 

 justified in following Dyar, and linking the Pterophorids with the 

 lower superfamilies of the stirps under consideration. 



Having briefly discussed the general relationship of the lower 

 superfamilies of this stirps to each other, it may now be of advantage to 

 examine, in more detail, the characters offered by the egg, larva and 

 pupa. 



The Sphingo-Micropterygid stirps, we have already stated, is 

 characterised by the possession of a flat egg, i.e., an egg with the 

 micropyle at the end of the long, horizontal axis. The egg has three 

 axes of different lengths, of which the micropylar is the longest, and 

 the vertical the shortest. The surface is generally smooth, the 

 sculpturing very slight and shallow, the shell thin, the texture tending 

 to be delicate, and it has both ends of pretty equal size, not being 

 more narrowed towards the micropylar than it is at the opposite end. 

 The Anthrocerid, Pterophorid, and Sphingid eggs, are, however, 

 much more delicate than those of the Lasiocampid and allied branches 

 of the stirps. Although the Eucleid egg is hardly typical for this 

 group, being soft, scale-like, and somewhat flattened, and, in these 

 respects, resembling closely the Tortricid egg, Chapman says that " the 

 type of egg described above, as characteristic of the Sphingo- 

 Micropterygid stirps, is so similar to that obtaining in the Anthrocerids 

 (Zygaenids) and Megalopygids (Cochliopodids), that the assumption 

 may be made that the stirps originated in these families." 



The egg of the Megalopygidae (teste Packard) does not appear to us to 

 be so different from what one might have supposed to belong to the most 

 generalised form of this stirps. As represented by Lagoa crispata, the 

 micropylar length : the other horizontal diameter : : 3|- : 1, the height 

 is, however, reduced to the least possible dimensions. Still, it is 

 essentially a flat egg in all its characters, with three unequal axes ; 

 of which the one representing the thickness is the least. We have, 

 elsewhere, remarked on its similarity to the Anthrocerid egg, and on 

 its being covered with silky hairs, as in some Lasiocampids — Trichiura 

 crataegi, Erioyaster lanestris, etc. 



There is no typical larva for this stirps, that of every superfamily 

 having been specialised (or modified) in its own particular direction. 

 The Micropterygid larva (like the egg) is quite sui generis, but exhibits, 

 as already detailed, some remarkable parallels with that of the 

 Eucleids. The Nepticulid larva, feeding on the parenchyma of the 

 leaves, is a mining whitish-coloured grub, with nine pairs of hookless 

 discs on the abdominal segments. The Eucleid (Cochliopodid) larva 

 has been specialised in many ways, the most remarkable of which is, 

 however, in the substitution of crawling discs for prolegs. The 

 Anthrocerid and some Pterophorid larvte have been specialised in the 

 union of tubercles i + ii and iv + v into large hair-bearing warts similar 

 to iii, so that there are three large warts on either side of each segment. 

 The Agdistis larva is further specialised by the development of a 

 caudal horn on abdominal segment 9 (not 8, as in the Sphingids). 



