40 Mr. J. O. Westwood on a gregarious 



Another interesting inquiry arises as to the manner in which this 

 nest is enlarged from time to time by its inhabitants, as its general 

 form and appearance do not exhibit any trace of additions*. 



This principle of sociality has been ascertained to exist in very 

 few other species of butterflies ; examples of it occurring in the Va- 

 nessa Urticce and V. Id upon nettles, and also in Meliteea Cinxia upon 

 the plantain — but their nests are of the slightest texture. 



The inclosed chrysalides were suspended by the tail, no girth 

 being fastened around their bodies as in the white butterflies. In 

 this respect, therefore, they resemble the VanesscE; but the chrysalides 

 have no angular projections. 



Description of the Pupa. — ^I'hey are about four fifths of an inch 

 long, and of a reddish brown uniform colour. The anal extremity 

 is terminated by a flattened slightly bent plate, armed at the point 

 by numerous short bent spines, by which it is attached to the little 

 bundle of silk spun by the larva for its attachment. Beneath this 

 appears a nearly rounded raised plate, with a line in the centre, 

 which seems to cover the anus of the imago. The abdominal seg- 

 ments are rounded at the lateral margins, and gradually become nar- 

 rower to the tail. A slight keel runs along the ridge of the back of 

 the mesothorax, which is very convex. The head is terminated by 

 an obtuse point. The base of each of the upper wings is also a 

 little bulged out, forming an obtuse angle. 



The antennae are laid along the margin of the wings : next to the 

 antennae are placed the middle legs, then the anterior legs, and in 

 the middle the two divisions of the maxillae, which reach as far as 

 the extremity of the legs. 



On dissecting several specimens of these chrysalides which were 

 ready to assume the imago state, I found no difficulty in raising these 

 parts from the body of the chrysalis, each on its distinct sheath f. I 



O'er thymy downs she bends her busy course, 



And many a stream allures her to its source. 



'T is noon, 't is night. That Eye so finely wrought, 



Beyond the search of sense, the soar of thought, 



Now vainly asks the scenes she left behind, 



Its orb so full, its vision so confined : — 



Who guides the patient pilgrim to her cell ? 



Who bids her soul with conscious triumph swell ? 



Hail, Memory ! hail ! thy universal reign 



Guards the least link of being's glorious chain. 

 * In the Bombyx processionea the larvae do not unite in forming a general habi- 

 tation until they have attained two thirds of their growth ; their nests, therefore, 

 will not need enlarging like those which live in society from their birth. The 

 Mexican butterfly may possess similar habits, which will account for the non-ap- 

 pearance of additions to the nest. 

 f See Kirby and Spence, vol. iii. p. 215. to the contrary. 



