284 RHYNCHOPHORA. 
work. He described under the name of Corthylus lobatus two examples which corre- 
spond with the specimens that we have received from Purula, though he not unnaturally 
reversed the sexual characters as here given. Under the name Corthylus signatus, 
Ferr., he grouped and purported to describe four specimens which actually belong to 
three different species. Two, mounted on the same card and labelled by him “2,6,” 
are respectively Pterocyclon bicolor (Ferr.) and Pterocyclon lobatum (Ferr.). The 
remaining pair, which by exclusion would be regarded as the types of Corthy/us 
signatus, prove, however, to be examples of P. chapuwisi (Kirsch), so that Corthylus 
signatus, although founded on the broad basis of three species, is dissolved into its 
elements and ceases to exist ! 
21. Pterocyclon sulcatum, sp. n. 
Mas. Elongatus, parum nitidus, ferrugineo-testaceus, capite, plaga discoidali prothoracis apicem versus 
elytrorum sutura, lateribus, apice nigricantibus; elytris medio fere a suture basi sulco communi 
utrinque seriato-tuberculato impressis, apice oblique retuso, obcordato, lateraliter marginato, margine 
utroque bituberculato. 
Long. 4 millim. 
Male. Elongate, subcylindrical, not very shining. Head black (the front concealed in the type); antennz 
testaceous, the club darker, oblong-oval, with curved sutures, not fringed. Prothorax oblong, its apical 
border obtusely rounded and crenate, the sides slightly rounded, the hind angles subrectangular, the 
base truncate; surface rounded from base to apex, more strongly in front, with no defined median 
elevation, ferruginous-testaceous, the apical half occupied by a large blackish patch not reaching the 
margins, scantily hairy and rather finely asperate, the asperities rapidly decreasing in size posteriorly, 
the basal half dull, obsoletely punctate. Scutellum small, rounded, black. Elytra scarcely so wide as 
the prothorax and one-half longer, subtruncate at base, with rounded humeral angles, the sides 
convergent from the middle to the apical flexure, where they are strongly ineurved by a rounded angle, 
the apical margins being subtransverse externally and conjointly excised in a shallow, curved, median 
emargination; surface ferruginous-testaceous, the suture, lateral limb, and apex blackish, moderately 
shining, subrugulose and obsoletely punctate, sulcate along the suture from shortly behind the scutellum, 
the sulcus not deep, rugose, with a series of small tubercles on either side; declivity obliquely retuse, 
beginning at the apical fourth, obcordate, the lateral and inferior margins defined, thickened above and 
below the middle, the thickenings each crowned with a small, pointed, setiferous tubercle, the fundus 
opaque, obsoletely punctured, with the sutural margins subelevated. Underside fuscous, the abdomen 
and legs testaceous. 
Hab. Panama, Volcan de Chiriqui (Champion). 
One example. The peculiar structure of the elytra in this species indicates an 
affinity with P. ferrari, though, as the type of that insect is of the opposite sex, no 
comparison can be made with the characters exhibited by its head and antenne. 
P. sulcatum is distinguished by its larger size and the distinctly retuse elytral apex, 
the side-margins of which are defined. 
22. Pterocyclon ferrarii, sp.n. (Tab. VIII. fig. 23, 2, head from in front.) 
Fem. Oblonga, subnitida, fusco-testacea, capite, prothoracis dorso ad apicem, elytrorum lateribus fusco-nigris ; 
fronte plaga longitudinali nitida, elevata, pilis longis prorsus directis insuper densioribus marginata ; 
