142 THE BUTTERFLY VIVARIUM. 



ingenious fashion to undergo the change to the chry- 

 salis, which will remain suspended after the Cater- 

 pillar skin drops off, as represented at No. 3, in the 

 same Plate. 



The small Blue Butterfly (No. 4) in the same 

 Plate, is one of our numerous JPolyommati* , a pretty 

 genus, so named from the Argus-like number of 

 eyes, or rather eye-like marks, on the under side of 

 their wings. It is the species named Polyommatus 

 Alexis, the common blue Butterfly. The Cater- 

 pillar of this pretty insect feeds upon different 

 plants of the trefoil family, the one engraved being 

 the cultivated Lucerne, Medicago Sativo, remark- 

 able, like all its genus, for the curious twisting of 

 the seed-vessels. 



No. 5, in the same Plate, is the female of P. 

 Alexis, which wears a robe of matronly brown, in- 

 stead of the bright azure of its mate. Its wings 

 are represented as raised, in order to exhibit the 

 disposition of the eye-like markings which have 

 given the name to this genus. 



At No. 6 is represented an example of a cu- 

 rious aberration which this family is subject to. 

 It is an individual of the species Polyommatus 

 Alexis, having on one side of the body the azure 

 * From polus (ttoXws) many, and omnia (o/u/xa) an eye. 



