462 STAPHYLINIDA. 
punctuation similar to that of the head. Elytra closely and finely punctate, not 
shining. Hind body densely and extremely finely punctate, the transverse impression 
at the base of each of the basal four segments deep, but with only indistinct crenate 
punctuation. 
The male front tarsi are much dilated, and there is a broad not deep emargination on 
the last ventral plate ; the front tarsi of the female are a good deal dilated. 
HOLISUS. 
Holisus, Erichson, Gen. et Spec. Staph. p. 298. 
Piestomorphus, Motschoulsky, Bull. Mosc. 1858, ii. p. 666, t. 1. f. d. 
This is a genus peculiar to Tropical America, where it ranges from Mexico to Rio de 
Janeiro, and has included hitherto eleven species. It is a very peculiar genus without 
any close ally, and its components are apparently insects of great rarity, being only 
occasionally met with, and then only in one or two examples; the species are appa- 
rently very closely allied, external sexual characters being confined to a difference in 
the medial lobe of the terminal armature; so that under these circumstances the species 
can only be ,at present very imperfectly differentiated. Mr. Champion tells me that 
these insects are subcortical in their habits, as, indeed, might have been inferred from 
their very depressed flat form. 
1. Holisus protensus. 
Depressus, nigerrimus, nitidus; coxis anterioribus rufis, tarsis piceis, capite oblongo-quadrato, crebrius fortiter 
punctato; thorace brevi; elytris crebre subtiliter punctatis. 
Long. 7 millim. 
Hab. GuateMALA, San Gerénimo, Rio Maria Linda (Champion). 
Head oblong, with numerous punctures on the front, and others on each side, leaving 
a rather large triangular space on the middle free from punctuation. Thorax short, a 
good deal shorter than broad, narrowed behind, hind angles very obtuse; there is a 
channel in the middle behind, and the lateral punctures are rather numerous. The 
elytra are not elongate, and their punctuation is fine and not close. The hind body is 
much narrowed behind, rather coarsely and not closely punctate. Metasternum chan- 
nelled in the middle behind, and with a rather large fovea on the channel. 
Three examples have been met with. The best characters for distinguishing the 
species are the moderately elongate head, the unusually stout antenne, and the intense 
black colour, with which the rufous anterior coxe form a strong contrast. 
2. Holisus confinis. 
Depressus, nigro-piceus, nitidus ; tarsis piceis, capite oblongo-quadrato, crebrius fortiter punctato ; thorace brevi ; 
elytris crebrius subtiliusque punctatis. 
Long. 7 millim. 
