PTEROCYCLON. 283 
None of the North-American species referred by Leconte to the subgenus Cosmo- 
corynus have any connection with it; they all belong to Division I. 
20. Pterocyclon lobatum. (Tab. VIII. figg. 21, apex of elytra, ¢ ; 22, 2: 
22 a, head.) 
Corthylus lobatus, Ferr. Borkenk. p. 57, 3 2 (lege 9 go)". 
Corthylus signatus, Ferr. loc. cit. p. 56 (pars) *. 
Subcylindricum, testaceum, capite, prothoracis antica parte, elytrorum lateribus et apice fusco-piceis; elytris 
postice angustatis, oblique excavato-retusis, ambitu utrinque 3-dentato, dente superno acuto. 
Long. 3°3 millim. 
Mas. Fronte inermi ; apice elytrorum profundius excavato, acutius marginato, dente 2° rectangulo. 
Fem. Fronte excavata, cornu recurvo supra os armata; claya antennali lata, ciliata ; apice elytrorum minus 
excavato, obtusius marginato, dente 2° obtuso. 
Moderately elongate, subcylindrical, moderately shining. Head fusco-testaceous; the front (3) convex, 
glabrous, shining, strongly punctured laterally, nearly smooth in the middle and subimpressed over the 
mouth ; the front (2) excavate to the eyes, the impression elevated in the middle and furnished with a 
dense brush of forwardly-directed hairs, and armed over the mouth with a curved horn, projecting 
forwards and slightly recurved and thickened at the tip; antenne testaceous, the club with nearly 
transverse sutures, narrow (¢) and not fringed, broader (@ ) and fringed on the upper border, the hairs 
neither long nor numerous. Prothorax longer than broad, obtusely rounded in front, the sides 
subparallel from the anterior third to the truncate base, the hind angles rounded, the apical margin (3) 
with a dense villous fringe of curled hairs formed by the elongation and thickening of the usually 
inconspicuous intramarginal cilia; surface gradually declivous before the middle, fusco-testaceous, the 
apical third deeply infuscate and finely asperate, the posterior two-thirds dull, with minute sparse 
punctures. Scutellum triangular, testaceous, with black margins. Elytra scarcely as wide as the 
prothorax and about one-third longer, slightly oblique at the base, the sides very feebly curved, 
convergent behind the middle, inflexed behind in a rounded angle to the separately-rounded apical 
margins, which form a wide, shallow, sutural emargination; surface subcylindrical, obliquely excavate - 
at the apex, with the suture impressed before the declivity, fusco-piceous, the basal half more or less 
testaceous, moderately shining, with indistinct rows of minute punctures ; excavation ( 3) rather deep, 
obcordate, shining, punctured, with the margins of the suture raised; side-margins acute, narrowly 
divaricate above at the suture, and armed with three teeth on each side, the first acute at the superior 
angle, separated by a notch from the second tooth, which is above the middle, and is subrectangular 
when seen from the side, the third tooth small and tuberculiform, separated by a shallow curve from 
the second ; excavation (? ) shallower and less oblique, with the teeth shorter, the second obtuse when 
seen from the side, the lateral margin not acute below it. Underside and legs pallid testaceous. 
Hab. Guatemaa, Purula (Champion).—VunezuEta (Moritz, in Mus. Vind. Ces.} 2), 
Three specimens. The structure of the head in the female shows a strong 
resemblance to that found in P. cristatum (Ferr.) and P. ferrarii, except that both 
these insects want the frontal horn; the fringe down the middle of the forehead 
is composed of a double vertical row of hairs curled outwards on each side, and is 
evidently homologous with the vertical rows which in those two species margin the 
shining median elevation, here obliterated. The development in the female of the 
intramarginal fringe of the front of the thorax is a novel sexual feature, so far as 
this family is concerned. 
The nomenclature of this species amusingly illustrates the character of Ferrari’s 
200 2 
