1 66 Studies in the Theory of Descent. 



in these young caterpillars we have preserved to 

 us the parent-form, extinct for centuries, of the 



Burmeister, in his recently published " Le'pidopteres de la 

 Republique Argentine," figures the young stages of species of 

 Catigo, Opsiphanes, Callidryas, Philampelus, &c. Messrs. 

 Hellins and Buckler have figured and described the early stages 

 of large numbers of the caterpillars of British Lepidoptera, but 

 their figures remain unpublished. The larvae of many of our 

 native species belonging to the genera Liparis, Tceniocampa, 

 Epunda, Cymatophora, Calocampa, &c., are dull when young, 

 but become brightly coloured at the last moult. Such changes 

 of colour are probably associated with some change, either in 

 the habits or in the environment ; and a careful study of the 

 ontogenetic development of such species in connection with 

 their life-history would furnish results of great value to the 

 present inquiry. The same remarks apply to those Noctucz 

 larvae which are brightly coloured in their young stages, and 

 become dull when adult. 



Among other papers which may be considered as contribu- 

 tions to the present subject, I may mention the following : 

 In 1864 Capt. Hutton published a paper, '''On the Reversion 

 and Restoration of the Silkworm, Part II. " (Trans. Ent. Soc. 

 1864, p. 295), in which he describes the various stages of 

 development of several species of Bombycida. In 1867 

 G. Semper published accounts of the early stages of several 

 Sphinx-larvae (" Beitrage zur Entwicklungsgeschichte einiger 

 ostasiatischer Schmetterlinge," Verhandl. k.k. Zoolog.-botan. 

 Gesell. in Wien, vol. xvii.). The question as to the number 

 of claspers in young Noctucz larvae has been raised in notes 

 by Dr. F. Buchanan White (" Ent. Mo. Mag.," vol. v. p. 204) and 

 B. Lockyer (" Entomologist," 1871, p. 438). A valuable paper, 

 " On the Embryonic Larvae of Butterflies," was published in 

 1871 by S. H. Scudder (" Ent. Mo. Mag.," vol. viii. p. 122). For 

 remarks on the development of the larva of Papilio Metope, 

 see J. P. Mansel Weale in Trans. Ent. -Soc., 1874, p. 131, and 

 PI. I. ; also this author on the young sta,ges of the larva 

 of Gynanisa fsis, Trans. Ent. Soc., 1878, p. 184. For an 



