THE SHORT-TAILED BLUE. 1 57 



one at Wrington, about twelve miles north of Bristol, in 1895 

 or 1896. 



The following details of the early stages are obtained from 

 Mr. Frohawk's life-history of the species published in the 

 Entomologist for October, 1904. The egg (Plate 102, figured 

 from a photomicrograph by Mr. Tonge) is of a pale greenish- 

 blue, but varies both in the extent of the ground colour and in 

 the structure of the reticulations, which are white, resembling 

 frosted glass. 



The full-grown caterpillar (August 23rd) measures § inch in 

 length. It is of the usual wood-louse shape, with only a very 

 shallow furrow on the back, bordered on each side by a fringe 

 of spinous bristles, which vary in length ; the whole surface is 

 densely studded with shorter but similarly formed whitish or 

 brownish bristles. The ground colour is pale green, with a 

 darker green stripe along the centre of the back, and fainter 

 green oblique stripes on the sides. The head is black and 

 shining, and is hidden under the first ring when the caterpillar 

 is not feeding or moving about. 



The caterpillars hatched on July 30th, from eggs that were 

 laid in the South of France on July 24th, and were reared on 

 bird's-foot trefoil (Lotus corniculatus), of which they ate the 

 flowers, seeds, and leaves. 



The chrysalis, which is attached to the food-plant by a silk 

 pad at the tail and a thread round the body, is pale green and 

 very finely reticulated ; the wing-cases are rather whiter green, 

 sprinkled with minute black specks, and the veins are white ; 

 there is a blackish line along the centre of the back, but this 

 is only well defined on the head and thorax. The whole 

 surface, except the wings, is sprinkled with slightly curved and 

 moderately long white hairs. 



The butterfly emerges in about ten to fourteen days, according 

 to temperature. 



The male is violet-blue with the veins rather darker ; the 



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