From these two species I have formed the present genus, the characters of which will distinguish it from that of _Haetera_ (Fabr.), a scanty genus confined to South America; and this seems to occupy its place in India: both will come in the natural family of _Hipparchidae_. Only one specimen (a male) exists in Dr. Horsfield's collections; I could not therefore dissect the mouth, &c. On the inner borders of the inferior wings is a lengthened tuft of fine hairs: the _anus_ beneath has on each side an obtuse lengthened process, partially attached, and which appears to supply the place of the lateral valves. It is represented on a sprig of GAERTNERA _racemosa_, which, although differing slightly from the figure of Dr. Roxburgh's Coromandel Plants, p. 19. t. 18, Dr. Horsfield considers as the same plant. The Javanese name is _Kakas_. * * * * * Pl. 12 [Illustration] GOBIUS Suerii. _Suerian Goby._ * * * * * GENERIC CHARACTER. _Caput parvum. Oculi approximati. Pinnae dorsales duae, radiis flexilibus: ventrales conjunctae, infundibuliformes. Branchiarum apertura contracta, membrana 4-radiata._ Typus Genericus _Gobius niger_. Pennant. Head small. Eyes approximating. Dorsal fins two, the rays flexible. Ventral fins united into the form of a funnel. Gill aperture contracted, the membrane four-rayed. Generic Type _Gobius niger_. Pennant. * * * * * SPECIFIC CHARACTER. _G. olivaceus, cauda atro-purpurea. Capite, operculis, pinna dorsali et caudali longitudinaliter flavo-lineatis._ Olivaceous Goby. Tail obscure purple. Head, gills, dorsal and caudal fins with yellow longitudinal lines. Gobius Suerii. _Risso Icth. p._ 387. _pl._ 11. _fig._ 43. * * * * * This beautiful little fish never exceeds the size here represented. It is not uncommon on the coast of Sicily in the spring months: it has likewise been discovered on the shores of Nice by Risso, who is its first describer: his figure, however, is so remarkably bad, that it would be impossible to recognise it but for his description: in fact, the fish is so delicate, that unless the fins are very carefully expanded in water their form and colouring will never be seen correctly. It has been named after M. C. A. Le Sueur (who accompanied Peron in the French circumnavigation), an able zoologist and most inimitable draftsman and engraver.