AND TIIETR TRANSFORMATIONS. 



Ill 



DESCRIPTION OF PLATE XXXV. 



Insects. — Fifr. I. Polyommatus Eros. 2. Showing the under side. 



,, Fig. 3. Polyommatus Porylas. 4. The female. 5. Showing the under side. 



Plants. — Figs. 6 and 7. Hippoerepis eomosa (the horse-shoe Vetch.) 



I have not met with any British specimens of either of these species, those marked Dorylas in many collections being merely varieties of 

 Adonis ; and I have seen small varieties of Argus marked Eros. It seems doubtful whether the true sjiecies has ever been found in thiscountry • 

 I therefore give the figures of Hiibner to enable collectors to compare specimens, which they may suppose to be cither of these species. II.N.H. 



SPECIES 10.— POLYOMMATUS EROS. THE PALE BLUE HUTTERFLV. 



Plate .\,\.\v. lig, 1 — 2. 



Synonymes Lyccena Eros^ Ochsenheinur, -I, p. "^li. 



Polyommatus Eros, Jermyn, Stcph. III. Ilaust. I, p. 93. Wood, 

 Ind. Ent. t. 3, fig. 70, $, 5. 



Arfjus Eros, Boisduval, Icones Hist. Lcp. pi. 14, fig. 4 — 6. 

 Vapilio Tilhonus, Hiibner, Pap. pi. 108, fig. 555, 550, S- 

 Haworth in Ent. Trans. 1. 334. 



The expansion of the wings of this doubtful British species is rather less than an inch and a quarter. The 

 upper surface of the wings in the males is of a pale azurine blue, with a silvery or greenish tinge, which is not 

 found in the allied species, P. Dorylas. The fringe is white, and separated from the gi-ound colour of the wings 

 by a black border, which is broader than in Dorjlas, and which extends slightly upwards along the tips of the 

 veins, especially in the under wings, which thus assume the appearance of having the margin spotted with black. 



The under side of the wings has considerable resemblance with Alexis in the ground colour and arrangement 

 of the ocelli and markings ; the ground colour being brownish grey, with the base saturated with greenish blue. 

 The fringe is separated from the ground colour by a slender black edge, preceded by marginal lunulcs of pale 

 yellowish orange, within each of which is a black arch, and on the opposite side a small black spot. These 

 fulvous markings are more indistinct on the upper wings ; their black anterior part is, on the contrary, more 

 strongly marked. Between the mark at the extremity of the discoidal cell of the f.jre wings (which is nearly the 

 same as in Alexis) and the fulvous lunules, is a range of ocollatcd spots ; the discoidal spot is preceded by an 

 oeellatod spot (Boisduval figures two such basal spots) in the fore wings, and in the hind wings by a row of four 

 (or three) similar ocelli, placed ui)on the greenish part of the base, as in Alexis. The under side of the breast 

 and legs are of a greenish grey, and tliat of the abdomen white ; the thorax and the under side of the abdomen 

 are blue. 



The female differs from the male almost in the same manner as in Alexis ; some specimens being entirely 

 brown, and others saturated with blue from the base to beyond the middle ; some again have only some blue 

 atoms at the base, and along the inner edge of the fore wings. The ground colour of tiie wings is rather black 

 than brown, with a central black limule. The extremity of the hind wings is ordinarily marked with a row of 

 Innules, fulvous within, black in the middle, and edged externally with white. The under side scarcely differs 

 from that of the male, except that the fulvous spots are rather brighter coloured. 



On the Continent this is a rare species, being found on the Ali-s of Valois, Tp-ol, and France ; Mount Ccnis 

 and the environs of Digno and of Gap have been recorded as its localities. It is therefore doubtful whether 

 Messrs. Haworth and Stephens, who have introduced this species into the English catalogues, may not have 

 mistaken some pale variety of Alexis for it. From that species it is at once known by the pectiliar pale upper 

 .surface of the wings of the male, with a dark border; antl from the female, by the much darker upper surface. 



