616 Mr. J. O. Westwood on the Paussidce, 
indeed it does not appear to me (on comparing the charac- 
ters of the different genera and the observations upon their 
respective affinities subsequently detailed,) that a natural linear 
or circular disposition can at present be traced in the few 
genera composing the family. Thus if we look to the variation 
in the number of joints in the antennae, we shall find Trochoi- 
deus intervening between Poussus and Pentaplatarthrus, and the 
latter between Platyrhopalus and Cerapterus. Again, if we re- 
gard the form of the antennae, we shall find the resemblance 
between Hylotorus and Paussus pilicornis Don., sufficient to 
separate Paussus from Pentaplatarthrus. Again, as the genera 
are numerically arranged above, the genus Hylotorus unnatu- 
rally separates the true Paussi with a continuous thorax from 
the Platyrhopali. If, also, we attempt to form a tabular ar- 
rangement of the genera from the structure of the trophi, — 
which, according to the Table given by Mr. MacLeay in the first 
part of the Ilorce Entomologies, are the organs susceptible of the 
least variation, and which consequently are of the first impor- 
tance in regulating the distribution of genera, — I fear that the 
result will not be more satisfactory : indeed, in some of the genera 
we are not acquainted with the structure of these organs. 
It appears, however, sufficiently natural to commence the 
series with Pentaplatarthrus, and to proceed thence to the true 
Paussi with a bipartite thorax ; thence, by means of P. spheero- 
cerus, to those with the thorax continuous, and to the Platyrho- 
pali, which evidently lead to the Cerapteri 
Genus 1 . Pentaplatarthrus* mild. 
Type of the Genus, P. paussoides mihi. 
Corpus subdepressum ; capite parvo ; thorace majori ; abdomine 
* Ilevrs, quinque; ttXutus, plat us ; upDpov, articulus ; — in allusion to the formation of 
the antennas. 
latiore 
