The interesting little butterfly represented on Plate 103 was not known to occur in Britain until 1885, when the Rev. O. Pickard Cambridge made the startling announcement that his sons had captured two specimens, a female on August 18th, and a male on August 20th of that year, the scene of capture being Bloxworth Heath, Dorset. Shortly after this fact was made public the Rev. J.S. St. John added a record of two males that he had discovered in a small collection of Lepidoptera made by Dr. Marsh, who stated that he had taken the specimens of _C. argiades_ in 1874, close to a small quarry near Frome. In addition to these a specimen, also recorded by Mr. Cambridge, was taken at Bournemouth in August, 1885; one is reported to have been captured at Blackpool, about 1860; and one at Wrington, about twelve miles north of Bristol, in 1895 or 1896. [Illustration: _Pl._ 104. =Brown Argus.= _Egg, natural size and enlarged; caterpillar and chrysalis; (a) Egg of "Scotch Argus" enlarged._ =Silver-studded Blue.= _Eggs, natural size and enlarged; caterpillar and chrysalids._] [Illustration: Pl. 105. =Silver-studded Blue.= 1, 2, 3 _male_; 4, 5, 6 _female_. =Brown Argus.= 10, 12 _male_; 7, 8, 9 _female_; 11, 13, 14 _male (Durham)_; 15 _male_, 16, 17 _female (Scotland)_.] 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 3/8 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.