I 1882.] 127 



others ranged from three to five, mx, Beven, and eight, overlapping each 

 other after the manner of pandalis, and like them presented a smooth 

 and greasy appearance. 



It was some time before I could detect on the Glechoma a mass 

 of eggs of precisely the same colour as the under-side of the leaf 

 where they adhered, and only when the mass presently in a slight 

 degree began to swell above the surrounding surface could I feel sure 

 it was composed of eggs, so perfect was the assimilation. 



In the interval while the eggs were maturing, Mr. Jeffrey and I 

 exchanged ideas with regard to the probable food-plant, so as to be 

 provided in readiness for the young larvae, and I found we were both 

 in accord in having fixed on the cruciferous plant as the most likely 

 among those above mentioned, to have induced the parent insects to 

 have parted with their eggs so freely, as they had, both on it and the 

 other leaves, probably from knowing the right food was present which 

 their progeny would unerringly find ; and we had good ground for 

 assuming this to be the case, as we remembered the fact that our only 

 two other British species of Fionea, viz. : forjicalis and margaritalis, 

 both feed on Gruciferce. 



Accordingly, when the eggs hatched on 2nd, 3rd, and 4th of 

 August, we were both prepared with Barharea vulgaris for the young 

 larvse, whose liking for it became soon unmistakeably apparent, for 

 though the other kinds of leaves were at first put with it, yet each 

 little larva iu turn found its way from them to the Barbarea, and crept 

 down the upper-side of the leaf to near the stalk and there rested, 

 and in course of an hour or two there became a numerous assemblage 

 of the little creatures lying in rows side by side most contentedly, 

 and where they afterwards began to feed, and to spread themselves in 

 small companies over the surface, but showed no disposition to wander 

 away from the leaf : thus they continued all through their subsequent 

 stages, unto the very end of their career, to be of exceptionably 

 amiable disposition, never interfering with one another when, as often 

 happened, some would be laid up to moult while their companions 

 were still by their side feeding, in such a sociable manner as to suggest 

 .the probability of their being in nature more or less gregarious. 



Very soon I experimented with six individuals by placing them 

 on leaves of Sincqns arvensis, and they contentedly throve on this food 

 as long as it could be supplied, but after a time these plants seeded so 

 rapidly that good leaves were difiicult to obtain, and as they would 

 not eat the seed pods of this or the other plant but only the leaves, I 

 eventually, after they had moulted, returned them to their former 



