DEROSOMUS.—CAUTODERUS. 169 
Hab. Mexico (Truqui, in coll. Fry), Saltillo in Coahuila (Dr. Palmer, Wickham), 
Durango (Dr. Palmer, in U.S. Nat. Mus.), Guanajuato (Sallé, Dugés), Dublan (Hay, 
in U.S. Nat. Mus.). 
Antenne, except the scape, only moderately long; scape extremely slender, yellow, 
with the apical incrassation fuscous ; first joint of funiculus’much thickened towards 
the extremity, rather longer than the following joint. Rostrum quite short, the eyes 
scarcely convex. Thorax cylindric, with very deep large punctures, clothed with pale 
scales and with erect, slender, black sete. Hlytra oval, moderately long, convex, with 
series of rather fine punctures, clothed with pale scales, and with more or less distinct 
dark marks, and with very fine, long, erect, black hairs. Legs piceous, hispid. 
The long sete and the deep, definite punctures on the thorax are the prominent 
characters of this species. ‘The insect seems to have been distributed by the late 
E. Dugés under the MS. name of Naupactus gratus. 
3. Derosomus scutellaris, sp. n. 
Elongatus, niger, viridi-griseo-squamosus ; elytris fusco-subvariegatis, setis erectis vestitis ; pedibus piceis ; 
antennis elongatis, testaceis, clava fusca. 
Long. 6 millim. 
Hab. Guatemata, Chimaltenango (Conradt). 
Antenne very long, the scape passing the front margin of the thorax; second joint 
of funiculus very long, but a good deal shorter than the first joint. Rostrum rather 
long, nasal incision deep; eyes oval. Thorax subcylindric, about as long as broad, 
covered with pallid scales that quite conceal the sculpture. Scutellum forming a black, 
shining tubercle. Elytra oval, rather convex, covered with greyish-green scales, and 
bearing moderately long, erect, fine hairs ; just before the middle an indefinite black 
fascia, interrupted at the suture, and also with a small black spot on each behind the 
middle; the strie and their punctures fine. Under surface squamose. Legs clothed 
with depressed pallid setosity, but without erect hairs. 
The two examples of this species are in very mutilated condition, but the species 
cannot fail to be recognized on account of the peculiar scutellum. 
CAUTODERUS, gen. nov. 
Antenne scapo elongato, cox posteriores late distantes ; abdomen segmentis secundis et tertiis longitudine 
subeequalibus. 
This genus agrees fairly well with Derosomus, except that the structure of the 
ventral plates is peculiar, the second segment being remarkably short, while there 
appears at first sight to’be a sixth ventral plate present at the extremity of the body ; 
this is, however, owing to the margins of the dorsal plate being deflexed to the ventral 
surface. The scrobes appear to be rather more sharply limited than they are in 
Derosomus. ‘Che absence of wings, though pretty certain, has not been verified. 
BIOL. CENTR.-AMER., Coleopt., Vol. IV. Pt. 38, May 1911. ZZ 
