1855.] 367 



b. 



2. H. t r i a n g u 1 a r i s, olivaceo-niger paulo conrexus, elongato-ovalis utrin- 

 que attenuatus, elytris punctorum seriebus solitis, alterisque duabus marginalibus 

 notatis, ad apicem coniunctim rotundatis, abdomine articulo lmo toto pubes- 

 cente reliquis nitidis medio subelevatis, singulis macula utrinque laterali trian- 

 gulari notatis, palpis antennisque piceis. Long. 1-3 1-45. 



Say, Journ. Acad. Nat. Sc. 3, 201. 



Hydrophilus lugubris Motsch. Bull. Mosc. 1845. 



Stethoxus mbsulcatus Lee. Proc. Acad. Nat. Sc. 7, 221. 



New York, Georgia, Texas, Nebraska, California. The anterior tarsi of the 

 male are more compressed than in the female, the last joint is dilated into a 

 sharp edged somewhat warped surface, and the claws are very unequal and not 

 toothed. In the female the claws are equal and* armed beneath with a large 

 acute tooth. The Californian specimens are scarcely perceptibly less attenuated 

 at each end, but do not seem sufficiently distioct to be considered a different 

 species. Col. Motschulsky, to whom I gave specimens for comparison, informs 

 me that it really is his H. lugubris, but that the short description given by him 

 is erroneous, having been drawn partly from another very different species from 

 the Philippine Islands. 



The last mentioned synonym was founded on two specimens from the Gila, 

 brought by Dr. Webb; at first sight they appeared to constitute a separate spe- 

 cies, the elytra being marked by several shallow but broad grooves; on examin- 

 ing them again, I am convinced that, although they agree in this character, it 

 must be regarded as a malformation ; as I find on the sternum and other parts 

 of the body corrugations which are the result of injury or disease ; and as in 

 form and in the pubescence of the abdomen they agree with the present species, 

 it would be proper to place them under it. 



c. 



3. H. 1 a t e r a 1 i s, elongato-ovalis utrinque attenuatus convexus, subtilissime 

 punctulatus atro seneus, nitidus, thoracis elytrisque lateribus anguste, metasterno, 

 pedum partibus palpis antennis clypeiqne angul s anticis fiavis. Long. '33. 



Herbst, Kafer, 7, 296 ; tab. 113, fig. 7. ? Fabr. Ent. Syst. 1, 183 ; Syst. El. 1, 251. 



Jlydrophdus nimbalus Say, Journ. Acad. Nat. Sc. 3, 203. 



New York, Georgia, Nebraska, Texas. Fabricius describes it from South 

 America, and the identity of his species with ours is therefore doubtful. The 

 legs vary in color; sometimes they are piceous with yellow margins ; sometimes 

 they are yellow with only the base of the thighs blackish. The prosternum is 

 sometimes yellow and sometimes black. The abdomen is entirely pubescent, and 

 usually appears black ; sometimes a range of small yellow spots is seen each 

 side near the margin. 



4. II. lim b al i s, 'olivaceo-seneus, subtilissime punctulatus, elongato-ovalis 

 convexus nitidus, capite antice, ore, mesosterno, pedibus, thoracis lateribus late, 

 elytrorum margine ante medium et saepe ante apicem latiore fiavis. Long. -31 

 34. 



California, at San Diego and the Colorado. Differs from the preceding by it3 

 more regularly elliptical form, acd by the broader yellow margin; that of the 

 elytra is wider at the base, and there appears triple ; at the mi' die it becomes 

 narrower, and immediately before the apex is frequently dilated by the addition 

 of several small linear spots. The prosternum is yellow, and the base of the 

 thighs black ; the abdomen each side is marked with an indistinct series of yel- 

 low spots. 



Varieties occur in which the sides of the elytra have three or four additional 

 indistinct yellow lines running from the broader anterior portion of the yellow 

 margin to the iip. 



5. II. c a 1 \ f o r n i c u s, elongato-ovalis, antice paulo magis attenuatus, con- 

 vexus, ater aenescens, nitidus subtiliter punctulatus, antennis palpis pedibusque 



i 



