682 On Aquatic Caimivorous Coleoptera or Dytiscidce. 



Fern., 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 fi-ont. I have seen very few individuals, mostly in bad condition. 



South America, (Cayenne). 969. 



1067. Thermonectes cuneatus, n. sp. — Convexiusculus, vix latus, anterius 

 angustatus, Ifevigatus, 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. 11l, lat. 6i m.m. 



Fern., nitida, elytris fere leevigatis, in medio ad basin punctis paucis subtilis- 

 simis. 



I have seen only a single individual of this species, which a])pears 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 epipleurse 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 raargine- 

 guttatus (No. 1070). 



Panama. 970. 



1068. Thermonectes batesi, n. sp. — Convexiusculus, iiaud latus, Isevigatus, 

 nitidissimus, niger, capite anterius et ante verticem, prothorace ad latera et trans- 

 versim in medio, elytris signaturis numerosis irregularibus, antenuis pedibusque 

 anterioribus testaceis ; epipleuris latis ; prosterni in medio minus lato. Long. 

 11, lat. 61 m.m. 



Fern., 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 irreo-u- 

 lar subajjical 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. 



