20 



IMPERFECT SOCIETIES OF INSECTS. 



be liable to have its stalk broken and to fall to the ground 

 with the first wind and there rot, in which state it would most 

 probably be destructive to the inclosed larvae. To obviate 

 this evil, the caterpillars when full fed have the remarkable 

 instinct to gnaw a hole about a quarter of an inch in diameter 

 through the hard shell of the fruit while it still remains on 

 the tree, and issuing through this hole to spin in common (as 

 it would seem) a silken web attached both to the stalk and 

 the base of the fruit, and sufficiently strong to support the 

 pomegranate from falling in the event of the stalk being 

 broken by the wind ; and having thus secured the stability of 

 their chamber, they retire again into it, and there undergo 

 their metamorphosis, the butterflies while their wings are still 

 unexpanded creeping out of the hole above mentioned, which 

 thus serves a second important purpose in their economy, of 

 allowing them a free passage in their perfect state through 

 the hard shell of the pomegranate, which, if this door in it 

 had not previously been provided by the caterpillar with its 

 jaws, would have proved a fatal prison to the butterfly which 

 has no such instruments. 1 



The most remarkable insects, however, that arrange under 

 this class of imperfect associates, are those that observe a par- 

 ticular order of march. Though they move without beat of 

 drum, they maintain as much regularity in their step as a file 

 of soldiers. It is a most agreeable sight, says one of Nature's 

 most favoured admirers, Bonnet, to see several hundreds of 

 the larvse of Clisiocampa neustria marching after each other, 

 some in straight lines, others in curves of various inflection, 

 resembling, from their fiery colour, a moving cord of gold 

 stretched upon a silken riband of the purest white ;° this 

 riband is the carpeted causeway that leads to their leafy 

 pasture from their nest. Equally amusing is the progress of 

 another moth, the Pityocampa, before noticed ; they march 

 together from their common citadel, consisting of pine leaves 

 united and inwoven with the silk which they spin, in a single 

 line : in following each other they describe a multitude of 



i Westwood in Trans. Ent. Soc. Loud. ii. 1. tab. 1. The Mexican butterfly, 

 (Eucheira socialis Westw. ) previously noticed, is also (as its name implies) social 

 in its larva state. 



