518 TRANSACTIONS OF THE 



tarsi abbreviated; elytra dark reddish-browu, iridescent, desti- 

 tute of punctures or strite, and attenuated behind. 



This seems to be a rare insect; I have seen but a single speci- 

 men. This new genus certainly differs from all the genera of 

 its family by the- form of the labial palpi, of the sternum and 

 poststernum, mucronate anterior tibia, &c. It closely approaches 

 the genus Noterm by the dilated labial [ 1 06 ] palpi, but differs 

 in havin"- those parts entire.. It also has some relation to Hali- 

 plus by the scales which conceal the origin of the posterior feet. 

 The proper situation of this new genus is between those two 

 genera, but it is unquestionably much more closely allied to the 

 former. 



HALIPLUS Latr. 

 Antennas ten-jointed; palpi subulate; scutel none; tarsi fili- 

 form, five-jointed, posterior thighs concealed at base by a clypei- 

 form scale ; body oval, thick. 



1. H. 15-PUNCTATUS. — Yellowish; thorax with two black 

 spots at base; elytra punctured and spotted with black. 



Length five-fortieths of an inch. 



Dytiscus maculatus Melsh. Catal. 



Body pale yellowish, with numerous dilated punctures, rounded 

 behind ; head immaculate ; thorax, a d^^tinct black spot each 

 side at base; elytra pale, with profoundly punctured striae, punc- 

 tures dilated, black, each elytron with six black dots placed 1, 2, 

 1, 2, the anterior one before the middle, the two succeeding ones 

 on the middle. 



The Dytiscus maculatus of Fabricius is altogether different from 

 this species ; it is a Colpnhetes. I have, however, thought 

 proper to reject the name maculatus as applied to this insect, 

 lest it should be confounded with the Fabrician insect by those 

 who adhere to his system or to that of Linne. 



[Belongs to Cnemidotus. — Leg.] 



2. H. TRiOPSis. — Pale yellowish ; thorax with a black spot 

 before ; elytra whitish, spotted with black. 



Length nearly three-twentieths of an inch. 

 Body pale yellowish, numerous dilated punctures; [107] 

 thorax with a largo conspicuous, deep black spot on the anterior 



[Vol. II. 



