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chidce is deceptive, for although they are pentamerous, yet the concealed joint is 
the first, and not, as in the Bostrichidce , the fourth. This is also the case in some 
genera of the Cleridce ; I, therefore, consider that the most natural situation of 
Apate is between this family and the Anobia , notwithstanding their resemblance to 
Bostrichus. This appears to be confirmed by the discovery by Professor Ratzeburg 
(who, as he has informed me, was long struck by the remarkable similarity of the 
holes bored by Apate and the Anobia ) of the larva of Apate , which in contradistinc¬ 
tion to the footless larvae of the Bostrichi, very much resembles those of the 
Anobia. 
The Bostrichidce may be divided into three very natural groups, characterized 
by the proportions of the head and thorax. In the first, the thorax is generally 
narrowed anteriorly, and encompasses the posterior portion of the head, leaving, 
however, the greater portion of it free, and for the reception of which there is a 
more or less considerable concavity beneath in front of the anterior coxae. The 
head is anteriorly elongated into a short thick rostrum. In the second group the 
globose head is wholly retractile within the thorax, which arches itself like a capu¬ 
chin over it, forming a deep emargination, beneath which, however, it is always 
even in the middle distinctly margined. The third group, lastly, which contains 
but one genus, has the thorax neither emarginate nor impressed beneath, and a 
free head frequently wider than the thorax. 
Group I.— Hylesines. 
Head exserted, the rostrum short, thick, and advanced. The antennae (ex¬ 
cepting Phloeotribus) inserted at the sides of the rostrum. Thorax beneath ante¬ 
riorly emarginate, with an impression (often obsolete) for the reception of the head. 
The third joint of the tarsus generally emarginate or bilobate. 
Genus I.— Hylastes, Erichs. The funiculus of the antennse seven-jointed; 
the knob four-jointed, orbiculate, compressed ; the tibise externally denticulated. 
This genus contains, 1. Hylastes ater , Payk., which is the Hylesinus piniperda 
of Fabricius, as the type, with nine other species. But it is further separated into 
two divisions, viz. :— a. The mesosternum truncated anteriorly; the third joint of 
the tarsus cordate, not dilatated: and b. The mesosternum conical and prominent; 
the third joint of the tarsus dilatated and bilobate. 
Genus II.— Hylurgus, Latr. The funiculus of the antennae six-jointed, the 
club quadriannulate, subglobose; the tibiae externally denticulated. The only 
known species is the H. ligniperda , Latr. 
Genus III.— Dendroctonus, Erichs. The funiculus of the antennae five- 
jointed, the knob quadriannulate, suborbiculate and compressed. The tibiae exter¬ 
nally denticulated. The type of this is the Bostr . micans of Kugelan, frequently 
mistaken for the Hyles. ligniperda, Fab.; besides which it contains, 2., Scoh 
terebrans y Oliv., 3., Dermestes piniperda , Lin., and two others. 
