62 Mr. C. J. Gahan— Notes on Oleridae. 



family, that tlie coxal cavities of the front legs are open ; 

 but this only shows that they had neglected to observe the 

 condition in a great many of the genera. 



Another character not yet made use of in the classifi- 

 cation of the Cleridse, but which will probably yield some 

 interesting results, is that which may be drawn from the 

 variations in the form &c. of the gular area on the head. 

 The gular sutures in some cases diverge posteriorly, so that 

 the gula is distinctly broader behind. In Tillus and many 

 other genera the gula is posteriorly divided off from the 

 sides of the head by a more or less narrow slit on each side, 

 and is continued back as a sort of free plate — a most unusual 

 condition in Coleoptera. A further modification of the 

 gula, characteristic of Clerus and those genera which, on 

 other grounds, I consider to be most nearly related to Clerus, 

 arises from the convergence of the sutures posteriorly, so 

 that the gula becomes very narrow at its hinder end. 

 Taking this character among others into consideration, I 

 believe that the following genera constitute a natural sub- 

 group within the group : — Colyphus, Cleronomus, Systeno- 

 deres, Pojcilochroa, Blaxima, Enoclerus (—Clerus of Schenk- 

 ling), Sallaa, Thanasimus, Tillicera, Clerus, Fab., Stigmatium, 

 Operculipkorus, Dasyceroclerus, Rhytidoclerus, Xestonotus, 

 Cyclotomocerus, Phaocyclotomus, Cardiostichus, Hemitrachys, 

 Omadius, and Corynommadius. Some of these genera are 

 widely separated in Lacordaire's arrangement ; and the same 

 is true, but to an even greater extent, of the arrangement 

 followed by Herr Schenkling. This subgroup (in which 

 the eyes are finely facetted and distinctly emarginate, the 

 acetabula of the front legs open behind, the tarsal claws 

 appendiculate at the base, and the last joint of the labial 

 palpi alone triangular) might come in the second place, the 

 first subgroup being constituted, as by Lacordaire, of those 

 genera in which the eyes are coarsely facetted, namely, 

 Axina, Priocera, Phlceocopus, Notoxus ( = Opilo) , Thanasi- 

 modes, Natalis, Cormodes, Gyponyx, Xenorthrius, Orthrius, 

 Aphelochroa, and (?) Erymanthus. In the last genus the 

 eyes are less coarse than in the others ; but yet not so fine 

 as in any of the genera of the remaining subgroups, ex* 

 cepting perhaps Thanero clerus, a genus to which 1 must 

 again refer. In these genera of the first subgroup the eyes 

 are as a rule feebly emarginate, sometimes almost entire; 

 the gular sutures diverge posteriorly ; the acetabula of the 

 front coxae are sometimes open, sometimes closed behind (in 

 the latter case the prosternum is usually expanded behind 



