7G 
THE ORDER OP OOLEOPTERA. 
Family XXIV. PSELAPIIIDJE. 
This is a family of minute beetles, generally less than a tenth of an 
inch in length, and is founded upon the genus Pselaphus, of Ilerbst, a 
term derived from the G reek pselaphus — to feel , in allusion to the greatly 
[Fig. 30.] 
developed palpi or feelers. They are found in the same 
situations as the Staphyliuidse, and resemble them in tlio 
shortness of the elytra, which usually cover only about half 
of the abdomen. In their form, however, they are wholly 
' different, being short thick-bodied beetles, with the abdo- 
men mitch larger than the thorax. The antenna: are clavate 
or capitate, and the maxillary palpi are very long and cla- 
vate, often equalling the antennae in length. The tarsi are 
.1, apparently two-jointed, but really three-jointed, the first 
ry'piimis "X tar- joint being very small. Like some of the larger Staphy- 
nutefeafuon 1 : linidae, these very small insects are predaceous in their 
ed^after W^tw! habits, subsisting upon acari and other minute animals. 
Some of them are found in ants’ nests. A synopsis of the Pselaphidae 
of the United States is given by Ur. E. Brendel, in the sixth volume of 
the Proceedings of the Ent. Soc. of Philadelphia, where eighty species 
are briefly described. 
Pselaphus 
Fourth Sub ’Section. PECTINICORNES. 
Antennas pectinate or comb-toothed ; subsist mostly upon tho sap of trees. 
Tribe VI. 
STAG-BEETLES. 
This sub-division and tribe are composed of the single family of Lu- 
canidae or Stag-beetles, distinguished by their pectinate or comb r toothed 
an ten me, which are also strongly geniculate or elbowed ; by the project- 
ing mandibles, which, in the males, are often enormously developed and 
branched, from which these insects have received their common name 
of Stag-beetles ; and by their size, which is never below the medium, 
and is generally large or very large, some species being upwards of two 
inches in length, including the mandibles. 
These insects are closely allied to the Lamellicorn beetles which fol- 
low, and are considered by many authors as holding the rank of only a 
sub division or family of the latter. Most modern authors, however, 
treat them separately. The principal differences may be expressed as 
follows : 
Pectinicornes. Antenme elbowed, the club composed of fixed trans- 
verse teeth. Mandibles of the males often greatly developed. The ner- 
vous ganglia distributed through tho abdomen as well as the thorax. 
Larva: without transverse wrinkles upon the segments ; anal opening 
lengthwise. 
