296 THE PAPILIONINA, OR BUTTERFLIES. 



In some particulars of their transformations, how- 

 ever, the Butterflies exhibit certain diflPerences, for 

 whilst the majority of their pupse are naked, a few 

 are enclosed in a regular silken cocoon, or even 

 employ the leaves of the plants on which they feed 

 for their protection; and of the former some are 

 simply suspended by the tail, whilst others increase 

 the security of their position by a slender belt round 

 the middle of the body, in the same way as the common 

 Cabbage Butterflies. The latter is the case with one 

 of the most beautiful of the British species, the Swal- 

 low-tailed Butterfly [Papilio Machaon), the only re- 

 presentative of the genuine Papiliones of modern 

 Entomologists which occurs in this country, where 

 indeed it is by no means common. The caterpillar, 

 which feeds upon the Fennel and Carrot, is of a green 

 colour, with black transverse bands and lines, of which 

 the former are adorned with reddish points ; the first 

 segment of the body is furnished with a singular ap- 

 pendage in the form of the letter V, which can be 

 pushed out and retracted at pleasure, at the same 

 time that the creature diffuses a disagreeable odour, 

 and this, with the threatening appearance of the pro- 

 truded appendages, is considered to have some influ- 

 ence in keeping off" the attacks of Ichneumons. The 

 chrysalis is attached to a branch of the plant in the 

 way already described, and is of a greenish or greyish 

 colour with a yellow streak on each side ; and the per- 

 fect insect, which makes its appearance in May and 

 July, is easily known by its great size and the pos- 

 session of a large tail on each of the hinder mngs. 

 Its principal colours are yellow and black, the latter 

 being generally more or less powdered with minute 

 yellow scales; the hinder margin of the hind wings 



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