Our first example is the Tailed Blue, known also as the Pea-pod Argus. The upper side of this insect ([Plate VI], fig. 10) is of a dull smoke colour, exhibiting purple-blue reflections, which are, in the female, confined to distinct blotches on the bases of the wings, but in the male are less noticeable, and extend over the whole surface. The hind margin of the hind wings has a row of spots, more or less distinct, and much more prominent in the female than in the male. The under side is beautifully marked with bands of fawn and grey, and with two spots of brilliant metallic green in the anal angle of the hind wings.
This butterfly abounds in the countries of South Europe, where the caterpillar feeds on the pods of certain leguminous plants; but
only a few stragglers have been taken in England, so that its reputation as a true Britisher is very uncertain. It is highly probable that the two or three specimens caught on our south coast were blown over from the Continent, and that the insect has never bred on this side of the Channel.
The Silver-studded Blue (Lycæna Ægon)
The upper surface of the male ([Plate VI], fig. 11) of this species is purple blue, with a black border on the hind margins of all wings. The female (fig. 12 of the same plate) is of a very dark smoky-brown colour, often with a bluish tinge, and has generally a row of orange spots near the hind margin of the hind wings.
The under side of both sexes is similar, and is illustrated in the accompanying woodcut. The ground colour is bluish grey, and is marked with a number of black spots surrounded by light rings. Along the hind margin of the hind wings is a row of orange spots, each bordered with black on the inner side, and with a silvery blue on the outer.