682 On Aquatic Carnivorous Coleoptera or Dytiscide. 
Fem., nitida elytris in medio ad basin punctis subtilibus impressis. 
The species is conspicuous by its form, which is very broad behind the middle, 
as well as by the comparatively abruptly defined post-medial yellow fascia of the 
elytra: the middle of the prosternum is very broad and thick, and very prominent 
in front. I have seen very few individuals, mostly in bad condition, 
South America, (Cayenne). 969. 
1067. Thermonectes cuneatus, n. sp.—Convexiusculus, vix latus, anterius 
angustatus, levigatus, nitidus, niger, capite anterius et in medio verticis, pro- 
thorace in medio et ad latera elytrorumque signaturis paucis, pedibusque anteriori- 
bus testaceis ; elytris plaga elongata humerali, fascia postmediali valde interrupta 
maculaque subapicali testaceis, epipleuris sat latis. Long. 111, lat. 64 m.m. 
Fem., nitida, elytris fere levigatis, in medio ad basin punctis paucis subtilis- 
simis. 
I have seen only a single individual of this species, which appears closely allied 
to D. interruptus, but is considerably smaller, with the medial yellow fascia and 
subapical mark a good deal diminished, while the humeral mark is more elongate : 
the posterior portion of the epipleurze is less dilated, and the punctuation on the 
elytra of the female is exceedingly indistinct. The markings of the upper surface 
give this species a resemblance to a very large individual of Acilius margine- 
guttatus (No. 1070). 
Panama. 970. 
1068. Thermonectes batesi, n. sp.—Convexiusculus, haud latus, levigatus, 
nitidissimus, niger, capite anterius et ante verticem, prothorace ad latera et trans- 
versim in medio, elytris signaturis numerosis irregularibus, antennis pedibusque 
anterioribus testaceis ; epipleuris latis ; prosterni in medio minus lato. Long. 
11, lat. 64 m.m. 
Fem., pernitida, elytris ad basin punctis numerosis impressis, prothorace utrinque 
parum conspicue punctato. 
The yellow marks on the elytra consist of a small humeral mark, and a very 
irregular curved series extending from the scutellum to the outer margin below 
the humeral spot ; beyond the middle a very irregular band, dilated in front about 
the suture, so as to form there an irregular discoidal pair of marks, and an irregu- 
lar subapical interrupted fascia. I have seen only a single individual; it is a 
female, and has the sexual sculpture on the base of the wing-cases rather dis- 
tinct, but the punctures less elongate than in the allies. The species will be easily 
identified amongst the allies, by its much varigated elytra, and the narrower 
prosternal process and middle part of the prosternum. 
South America, (Upper Amazons, Bates). 971. 
