On Aquatic Carnivjrous Coleoptera or Bi/tiscidce. 289 



Group I. A. 



92. Dytiscus maculosus, Germ. Laccophilus maculosus M.C. — Ovalis, latiusculus, 

 nitidus, testaceus, elytris fere impunctatis, pallidis, sed conspicue nigro-ornatis ; 

 coxis posterioribus plus minusve infuscatis. Long. 5|, lat. 3i m.m. 



The markings of the elytra are more distinct in this species than in the allies ; 

 their ground colour is pale yellow, but they are made dark by numerous minute 

 dots, these dots are absent from some places which thus form yellow spots, while 

 at the margins of these yellow spots the dark dots are condensed so as to form 

 black marks ; the pale marks form a fascia at the base which is, however, much 

 interrupted and rendered very irregular by longitudinal prolongations of the dark 

 marks ; at the side of each elytron are four very conspicuous pale marks, the second 

 from the base being largest, and the fourth is apical. 



In the male the four front tarsi are a good deal incrassate, and are furnished 

 beneath with hairs bearing cupules at their extremities ; the hind coxa bears a 

 curved series of fine lines or ridges commencing at the extremity of the metaster- 

 num : in the female there are also traces of this file, but they can only be detected 

 in this sex by a careful examination with a good glass. 



North America ; Lake Superior, Massachusetts, Hermit Lake, Pennsylvania, Georgia. (? South 

 America ; Ega, Amazons). 528. 



The specimens supjiosed to have been found at Ega by Mr. Bates are a good deal narrower than those 

 from North America, but I am unable to find any other difference : and I believe they are really from 

 North America. 



93. Laccophilus decipiens, Lee. M.C. — Ovalis, latus, minus depressus, nitidus, testa- 

 ceus, elytris fere impunctatis, gequaliter fusco-irroratis, maculis paucioribus minus 

 distinctis. Long. 5f, lat. 3 J m.m. 



The species is closely allied to Dytiscus maculosus (No. 92) but is rather larger, 

 broader and more convex, and is readily distinguished by the less variegate elytra, 

 from which the basal marks are entirely absent, and the marginal and sutural ones 

 are much less conspicuous. The sexual differences are very similar in the two 

 species. 



North America : California, Utah ; (Amer. lluss. teste Mannerheim). 529. 



94. Laccophilus proximus, Say. M.C, — Ovalis, latiusculus, nitidus, testaceus, 

 elytris fere impunctatis fuscis, signaturis pallidis minus distinctis. Long. 5^^, lat. 

 3 m.m. 



In the three individuals I have examined I can find no distinction from Dytiscus 

 maculosus (No. 92) except the darker colour and more indistinct markings of the 



