212 STAPHYLINIDA, 
1. Sceptobius dispar. (Tab. V. fig. 23, ¢ .) 
Fusco-niger, pedibus fusco-ferrugineis, antennis ferrugineo-testaceis, opacus, dense subtilissime pubescens, 
subtilissime punctatus. 
Long. 34 millim. 
Mas antennis pedibusque elongatis. 
Fem. antennis pedibusque mediocribus, illis rigidulis consolidatis. 
Hab. Mexico (Truqut). 
Antenne in the male nearly as long as the body, destitute of sete; third joint large ; 
terminal joints closely articulated, so as to have little mobility (as in many other 
Myrmecophilous Staphylinide); terminal joint very elongate, as long as the two 
preceding together. Head very finely, scarcely visibly punctulate. Thorax nearly as 
long as broad, a little narrowed behind; in the female rather shorter, and distinctly 
narrowed behind, scarcely visibly punctate, very finely pubescent. Elytra extremely 
short, especially at the suture, where they are not half so long as the thorax, extremely 
finely punctate. Hind body getting broader till the fifth segment is reached, excessively 
densely and finely punctate and pubescent. 
The differences between the sexes is very great. In the female the antenna, after 
the third joint, are abbreviated, and their joints amalgamated so as to form an elongate 
solid piece, the sutures between the joints, however, being visible ; the head is smaller 
than in the male, and more truncate behind, so as to be almost triangular in form; and 
the prothorax and afterbody are broader. ‘The legs in this sex are probably of ordinary 
size. In the male the middle and hind legs are elongate, the latter pair being specially 
large and remarkable, and apparently, from their form and the position they assume, 
not adapted for locomotion. The tibie are stout, and a little oblique-truncate externally 
at the extremity; the tarsi are large, and continue the direction of the tibie ; the basal 
joint is stout and very elongate, almost equal in length to the four following together, 
each of which is more slender than its predecessor; fourth joint small; fifth slender, 
almost equal in length to the second joint; claws very minute. In this sex there are 
no peculiar abdominal structures. 
The pair of this species in my collection were captured by Signor Truqui in Mexico ; 
and another pair, obtained from the collection of M. Sallé, is evidently from the same 
source. The specimens are so extremely fragile that very cautious investigation has 
caused the detachment of the larger part of what remained of the legs and antenne of 
the females. ‘That the species is Myrmecophilous is evident not only from the struc- 
ture, but from the fact that an ant is mounted along with one of the individuals in 
M. Sallé’s collection. 
FALAGONIA. 
Facie et summa affinitate generis Drusilla, Rey ; sed mesosternum aliter formatum. 
The insect for which the above generic name is proposed is very closely allied to the 
