On Aquatic Carniworous Coleoptera or Dytiscide. 679 
In the male, the most basal of the three larger palettes on the underside of the 
front feet is considerably larger than the other two. 
The black marks on the thorax are less extensive than in the allied species, the 
anterior one is placed a little behind the front margin, and is not interrupted in 
the middle even when most diminished, and is never connected with the posterior 
marks, which consist of two very closely placed lines joined at their extremities 
go as to enclose a yellow transverse line which is most frequently divided in 
the middle; when the black marks take a greater extension than usual, this 
enclosed yellow line may be entirely absent. The species varies much in size, and 
somewhat in the relative amounts of the black and yellow colours; and in the 
smallest females the sexual sculpture is nearly entirely absent; the punctures on 
the thorax appear however to be not quite so variable as the more conspicuous 
sculpture on the elytra. 
South America, Mexico, (Bahia, Petropolis, Para, Peru.) 964. 
1061. Dytiscus circumseriptus, Latr., Acilius cirewmseriptus, M.C_—Convexius- 
culus, parum latus, levigatus, nitidus, subtus niger, prosterno ex parte majore 
testaceo, supra testaceus, vertice nigro-signato, thorace anterius et posterius in medio 
nigro, elytris nigro-irroratis, irrorationibus post medium in fasciam transversam 
nigram condensatis, et post fasciam irregularibus, antennis pedibusque anterioribus 
testaceis, pedibus posterioribus extus nigris, femoribus externe late rufescentibus ; 
elytrorum epipleuris angustis. Long. 112, lat. 62 m.m. 
Fem., elytris in medio longitudinis punctis elongatis subtilibus impressis, pro- 
thorace versus latera punctis impressis minus subtilibus. 
In the male the three larger palettes of the undersurface of the front tarsi are 
of about one size, and not very large. ‘The fine impressed linear punctures on the 
wing-cases of the female form a broad patch extending from the base about two- 
thirds of the length of the elytra. 
In this species the transverse black mark on the thorax always attains respec- 
tively the front and hind margins, and so leaves yellow across the middle only a 
short stripe between them. 
The species varies a good deal in size, and in the greater or less condensation of 
the black spots of the upper surface, occasionally the sides of the hind body are 
obscurely spotted with yellow. The sculpture of the female is evidently variable, 
for there exists in Dejean’s collection an individual of that sex, which shows no 
trace of the impressions on the elytra, and very little of the thoracic punctuation. 
Widely distributed in the New World, from Mexico and the Antilles to Monte Video. 965. 
1062. Thermonectes depictus, (Reiche), n. sp.—Convexiusculus, latiusculus, 
levigatus, nitidus, subtus piceus, prosterno anterius rufescente, supra testaceus, 
