54 
INSECTA SAUNDERSIANA. 
towards the base of the elytra, and more widely and angularly emarginate 
in the middle of these organs, so that it appears to be more triangular at 
each side of the median emargination. The rostrum has nearly the same 
proportion as in Pt. elongatus; hut the head is at least as short and convex 
as in Pt. Columbianus. The eyes are more oblique in front, the face being 
more evidently narrowed towards the rostrum. The antennce of the most 
developed males are a little shorter than in the latter species, but longer 
and thinner than in the former. The thorax is proportionally shorter, 
broader and more rounded at the sides than in Pt. Columbianus: the 
median transverse elevation lying between the anterior and posterior 
impression is evident, while it is very obsolete in that species and in 
Pt. elongatus. The elytra , shorter and broader than in Pt. Columbianus , 
are also thicker as seen from the side; their upper depression is narrower 
and deeper; their narrowness behind is as slight, and their declivity 
behind as well as the form of the callosity are a little more indicated. 
The body beneath is certainly more convex, and the perpendicular height 
of the body is much thicker in proportion to the length of the elytra than 
in Pt. nebulosus , which is certainly the thickest and shortest of the three 
preceding species. 
Obs. —I have seen a number of specimens of this species, the type of 
which is in the cabinet of M. Chevrolat. 
Ptychoderes callosus ( Chevrolat ), Jekel. 
Parum elongatus , pro ratione generis lalus et convexus , dorso angusle 
parumque deplanatus ; niger, tomento infra sericeo alho-subvirescente, 
dorso in vitta communi lata irregulari parum determinata alba 
olivescente variegata, lateribus olivescente albido mixto tecto; maculis 
punctisque ordinariis disci olivescentibus ; rostro sat elongato ; capite 
pone oculos parum extenso , antice per oculos convexiusculos oblique 
angustato y inter illos convexo; thorace lato , longitudine parum 
angustiore , lateribus valde rotundatis; scutello transversim ovato; 
elytris convexis , dorso anguste leviterque depressis, longitrorsum con- 
vexiusculis, posterius ante callum oblique subconvexim declivibus , 
callo ante-apicali basi angusto , sat longo, tuber culiforme, sed libellarn 
perpendicularem apicis suboblique truncati non attingente; seg- 
mentis abdominis omnibus basi utrinque macula quadrata olivescente 
ornatis. 
