Mr. A. G. Butler on new Lepidoptera. 161 



sionally flattened or otherwise distorted. The foot is whitish 

 translacid, and may be extruded to a length more than equal- 

 ling that of the shell, the body being brought up to it with a 

 jerk, as in allied species. Full-grown examples are slightly 

 more equilateral and more angulate than young ones. 



The first example was found by Mr. Prestoe, the' colonial 

 botanist, when we were examining the weeds in a pond at 

 St. Ann, near Port of Spain, for Mollusca. 



Port of Spain, Trinidad. 

 January 8, 1867. 



XXVIII. — Descriptions of five new Genera and some new Species 

 of Satyride Lepidoptera, By Arthur G. Butler, F.Z.S., 

 Assistant, Zoological Department, British Museum. 



[Plate IV.] 



The genus Lasiommata of Westwood has* hitherto contained 

 Satyridse which differ in size, colouring, and structure. The type 

 of this genus appears to be the well-known L. ^geria of Lin- 

 naeus*; this insect, however, does not possess all the requisite 

 characters, nor, indeed, can I find any species that entirely answers 

 to the description of the genus. MegcBra certainly possesses a 

 pear-shaped club to the antennae: these are not, however, di- 

 stinctly annulated with white ; moreover the apical joint of the 

 palpi is somewhat elongate, and unlike that of yEgeria, . 



I propose in the present paper to separate the different struc- 

 tural forms under generic heads ; and as the characters of La- 

 siommata have necessarily been made very general, so as to in- 

 clude very widely distinct species f, I shall redescribe the genus, 

 and thereby, I hope, make it more defined. 



Genus Lasiommata [Pararge, Hubn.)J. 



Lasiommata^ part., Westwood. 



Alae anticse elongato-triangulares, costa plus minusve arcuata; 

 apice vix angulari ; margine postico apud apieem plerumque paulum 

 angulato ; margine interiore subrecto ; venis velut in Debe (nee 

 Arge) positis. 



* See Westwood & Humphrey's * British Butterflies,' p. 66 (1840). 



t See Gen. Diurn. Lepid. p. 385. "Antenna; straight, distinctly annu- 

 lated with white, not quite half the length of the fore wings, terminated 

 by a distinct, compressed, i)ear-shape<l chib, the tip bent outwards ; the 

 club, however, varies considerably in shape, being elongated and very 

 gradually formed in some of the exotic species' (L. ^gerial). 



J I am not quite satisfied that the genus Pararge of Hiibner's * Verzeich- 

 niss ' should not sui)ersede Lasiommata ; though not sufficiently charac- 

 terized, it certainly possesses the advantage of priority. 



