of the Lepidoptera Diurna of Latreille. 183 



reason to doubt, that in our present difficulties, more accurate 

 results will be derived by an attention to this state of the in- 

 sect, than can be expected from a paramount regard to the 

 larva. Entomologists have long ago remarked the following 

 variations in the form and suspension of diurnal pupae. 



1. Pupa suspended by the posterior exiremity. 2. Pupa 

 attached by the posterior extremity, but braced or supported 

 in a horizontal or vertical direction by a transverse thread. 

 3. Pupa attached like the last, but foliculated, or inclosed 

 within a leaf. Among these, two forms are conspicuous : — 

 1. Pupae elongated and angular. 2. Pupas obtuse and smooth. 

 Geoffroy and Latreille have not failed to draw a marked 

 distinction between such of the diurnal Lepidoptera as have 

 the anterior feet perfect, that is, distinctly furnished with claws, 

 and those which have the same feet imperfect, or not furnished 

 with claws. 



It is clear that in any attempt towards a natural arrange- 

 ment, all these variations must have their due weight, yet 

 without being used as circumscribing bounds. There is pre- 

 sumptive evidence to prove the truth of the assertion, " that 

 the variation of metamorphosis (or of any particular set of 

 organs) is only an index of the series of affinity, and not a 

 principle by which groups have been strictly circumscribed*." 

 On searching for that group which presents the most per- 

 fect development of organs, and at the same time is eminently 

 distinct from the other primary divisions of the Lepidoptera, 

 our attention is immediately fixed upon the genus Papilio of 

 modern authors. In these the larva is cruciform, the pupa 

 angulated and braced, and the perfect insect furnished in both 

 sexes with distinct nails on their anterior feet. These cha- 

 racters, strikingly exemplified in the typical groups [Papilio, 

 Fieri s, L.) are softened down, and in part exchanged for others 

 in the aberrant examples. In the genus Colias for instance, 

 the anterior feet are short, and the ungues small and weak : in 

 nais the club of the antennae is elongated and arched like 

 that of many i/(?5/>m(/<rp ; and in Parnasstis the pupa is smooth 

 and subfoliculated f . To this last genus we shall subsequently 

 have to call the reader's attention. 



By the short and weak leet of Colias, we are conducted to a 

 large and very important division, comprising many forms de- 

 fined by Fabricius, but classed by Latreille as the genus Nym- 

 phalis. If" strength of body, rapidity of flight, superiority of size, 

 or brilliancy ofcolouring, were sufficient to constitute the typical 



• Ilorw Knt. part ii. p. 45G. 



t liiitrcillc, Gen. Inst. See also Esper. vol. i. tab. 2. f. 1. 



perfections 



