SINDOLUS.—CHASMOGENUS. 73 
2. Sindolus mundus. 
Ovalis, sat convexus, livide ferrugineus, pernitidus; antennarum basi, palpis tarsisque testaceis ; palpis elon- 
gatis; capite thoraceque parum crebre punctatis ; elytris ad latera seriebus duabus punctorum, et ad apicem 
seriebus aliis brevissimis, praeterea fere impunctatis. 
Long. 23, lat. 13 lin. 
Hab. Mexico, Oaxaca (Hoge). 
This species is very similar to VS. optatus ; but the elytra are almost impunctate, except 
that they have two or three somewhat imperfect series of punctures near the lateral 
margins and the rudiments of six or seven other series at the apex. Only a single indi- 
vidual has been brought before me: it has a series of punctures on each of the wing- 
cases near the suture ; but this may possibly be accidental. The mesosternal lamina is 
very large; and the structural characters seem to be extremely similar to those of 
Sindolus optatus, except that the clypeal suture is very distinct, and that a longitudinal 
suture in the middle extends backwards from it. 
CHASMOGENUS. 
Genus Philydri et Helocharidis affine, sed mento aliter formato, anterius in medio regulariter impresso, mar- 
gine anteriore in medio late semicirculariter emarginato. Palpi maxillares elongati, graciles, ut in genere 
Helochuride formati; palpi labiales perbreves, articulo ultimo leviter sed distincte incrassato. Oculi 
prominuli. Mesosternum subarmatum. Tarsi omnes evidenter quinquearticulati, tenuissimi. 
I propose this genus for a curious little insect of very fragile structure, and in 
appearance as well as by its systematic characters very similar to Helochares and Phily- 
drus, but distinguished by a peculiarity of the mentum, inasmuch as the peculiar 
bent-in.or hollowed condition of this part seen in Helochares has here assumed the form 
of a definite impression, and in front is terminated by a broad curved emargination. 
The maxillary palpi are very elongate and slender, formed as in the genus Helochares ; 
the labial palpi are very short, and the terminal joint slightly but undoubtedly dilated. 
The mesosternum does not bear any distinct lamina, but is slightly prominent in a 
longitudinal manner along the middle; and the front of this prominence forms an edge, 
so that there really exists the rudiment of alamina. ‘The legs are very slender ; and the 
tarsi are evidently five-jointed, but extremely slender. There is a sutural stria on the 
wing-cases. ‘The glabrous submental area is limited to a mere slip at the front margin 
just behind the mentum. 
1. Chasmogenus fragilis, (Tab. II. fig. 13.) 
Oblongus, subdepressus, nitidissimus, piceus, prothoracis lateribus late pallidioribus ; elytris fere nigris, ad latera 
dilutioribus ; antennarum basi, palpis tarsisque testaceis, pedibus rufis ; capite thoraceque sparsim subtilius 
punctatis ; elytris fere levigatis, stria suturali impressa. 
Long. 13, lat. 3 lin. 
Hab. Guatemata, San Geronimo (Champion); Panama, Caldera, 1200 feet (Champion). 
The fragile, depressed, and oblong form and the very polished upper surface render 
BIOL. CENTR.-AMER., Coleopt., Vol. I. Pt. 2, October 1882. LL 
