The outline of this richly-ornamented insect perfectly corresponds to that of the preceding species, except that the hinder margin of the upper wings is scarcely concave. The whole disk is very brilliant blue with a tinge of green, surrounded by a black border, which is wide and sinuated on its inner edge in the female, and narrow in the other sex. The anal angle of each of the hinder wings bears a large blood-red mark, and the tails are black tipped with white. On the under side the green hue predominates, and the whole is thickly-powdered as it were with gold dust, giving it a very rich appearance. Near the middle both wings are traversed by a distinct black line, angular posteriorly, and bordered externally by pale blue: behind this, on the under wings, there is a broad deep red or ferruginous band, paler towards its hinder edge and sprinkled with blue atoms: the outer margin of all the wings is darker than the interior. Expansion of the wings about two inches. [Illustration: PLATE 27. _1. 2. Polyommatus Venus._ } Surinam _3. 4. ---- Achaeus._ } _Lizars sc._] POLYOMMATUS VENUS. PLATE XXVII. Figs. 1, 2. Pap. P. R. Venus, _Fabr. Mantissa_.--Hesperia R. Venus, _Fabr. Systema_.--Pap. Venus, _Herbst. Pap._ Pl. 294, fig. 1, 2. Pap. Imperialis, _Cramer_, Pl. 76. fig. E, F. This beautiful little insect is not unlike the preceding both in its form and colours. It belongs to a section of _Polyommatus_, in which the upper wings of the male are marked with an orbicular spot, of a cottony appearance, and frequently a good deal impressed. The expansion of the wings does not exceed an inch and a half. The colour of the surface is brilliant blue, the costa and outer margin of the wings black, and the disk of each marked with two ferruginous points in the male. Beneath, the colour is likewise green, richly glossed with golden yellow, the anterior portion of the under wings transversely streaked with narrow black marks. The tails are wholly black. All the examples hitherto brought to Europe seem to be from Surinam. POLYOMMATUS ACHÆUS. PLATE XXVII. Figs. 3, 4. Hisperia R. Achæus, _Fabr._--Pap. Achæus, _Cramer_, Pl. 352, fig. G, H.--_Herbst. Pap._ Pl. 297, figs. 3, 4. Nearly the same size as _P. Venus_, and also a native of Surinam. Upper side dark brown, the superior wings with two oval yellow spots on the disk of each, and two transverse curved streaks of the same colour on the inferior, the anal angle with a ferruginous spot. Under side yellow, with numerous ferruginous patches, each of which is ornamented with several small spots of golden-yellow, the outer border with a continuous ferruginous band bearing a series of golden-yellow elongated spots. Body brown above and yellowish beneath. GENUS THALIURA.