16 THE CLASSIFICATION OF INSECTS 



contrary, I am about to show that it is natural, that it agrees with inductions 

 derived from embryological studies, and that it is sustained by facts from various 

 quarters, though sotne of these facts have remained unnoticed and others have been 

 used unconsciously, or, at all events, never with a view to establish the proper 

 rank of Lepidoptera among themselves. 



There is one point in the early metamorphoses of Lepidoptera which is of great 

 importance in this respect ; I mean the condition of the larva of diurnal Lepidop- 

 tera. Among this family, there is not one species known with maggot-like cater- 

 pillars ; they are all provided with various kinds of organs of locomotion, legs and 

 prolegs, the last pair of which, again, generally differs from the middle prolegs. 

 They are all colored, and their color is bright and varied. Now this state of 

 development, in which the diurnal Lepidoptera escape from the egg, is already a 

 higher condition than that from which other families among Lepidoptera begin, 

 or of which there are, at least, some examples in various other families. For, 

 even among Sphinges, Ave have naked larvse, livmg in the dark, with an obscure, 

 almost colorless skin. And among nocturnal Lepidoptera the number of those 

 types in which the larvae are more or less maggot-like is still greater, while among 

 diurnal Lepidoptera all begin with a character of most perfect caterpillars. Again, 

 it is among the nocturnal Lepidoptera that we find the greater number of larvae 

 resembling Worms proper, or having characters most strongly analogous to those 

 of true Worms. 



If, from this state of growth, and the arguments it affords in favor of our view, 

 we pass to the investigation of the pupa, we find here, again, arguments which go to 

 show that the pupge of the diurnal Lepidoptera have higher characters than those 

 of Sphinges and Moths, as I shall presently show. The caterpillars of Lepidoptera, 

 however highly organized, correspond to that stage of development of Insects in 

 general which we call their larval state, and this homology may be traced through 

 the whole class, however diversified the larvse of various orders may be. This 

 larval condition corresponds to the state of structure characteristic of the class of 

 Worms. The larvae of Insects are, indeed, truly homologous to the class of Worms 

 in structure, while their pupae correspond in the same manner to the class of Crus- 

 tacea, as I shall show more fully hereafter. If this be the case, let us now compare 

 the pupae of the different families of Lepidoptera. 



Among the nocturnal species, even including the Sphinges, we have those in 

 which the body is smooth, more or less cylindrical, elongated, the abdomen more 

 free and conspicuous, the thorax and head shorter ; while the pupae of all Papil- 

 ionidae are angular, the head prominent, the head-chest proportionally longer than 

 the abdomen, with all sorts of protuberances, projecting angles, and spines, and 

 the abdomen comparatively reduced, — characters which seem to me to indicate a 

 remote analogy between the peculiarities characteristic of the long-tailed and short- 

 tailed Crustacea, the relative position of which has long been determined. If, there- 

 fore, the general analogy between pupae and Crustacea be once granted, the more 

 special relation of the diurnal pupae and Crabs, and that of Moths and Lobsters, must 

 also be granted, and the superiority of the pupae of diurnal Lepidoptera over the 



