REMARKS ON THE COLEOPTERA. 225 



APHODITJS III. curtus Hd. I I. 105. 



91 hyperboreus. OXYOMUS Lair. 

 omissus. \nec Say. strigatus. 



concavus Hd. J. Ac. N. S. 1, 103, Aph. strigatus Say. J. Ac. 3, 212. 



pinguis Hd. 1. c. 103. RHYSSEMUS Muls. 



92 angularis. M cribrosus. 



63 consentaneus. .ZEGiALiA Encycl. 



4-tuberculatus Fabr. ^lacustris. 



91 A. hyperboreus. Oblongus rufo-piceus nitidus, capite nigro, thorace lateribus 

 punctate, disco lasvissimo, angulis posticis obtusis rotundatis, basi vis marginata 

 utrinque obliqua, nigro lateribus obsolete rufis, elytris crenato-striatis, interstitiis fere 

 planis, luevissimis. Long. -3. Pic. The clypeus is smooth, with only a few points at 

 the side, the margin reflexed, and slightly emarginate. Belongs to Erichson's di- 

 vision D, as well as the three following species. It is very similar to A. omissus, but dis- 

 tinguished (apart from color) by the smooth clypeus and impunctured elytra. I have 

 changed the name of the next species, as it cannot be Mr. Say's A. concavus : that author 

 makes no mention of the large scutellum, which he would not have failed to observe in 

 comparison with other species. I know not how Mr. Haldeman omitted this character 

 which would serve at once to distinguish the species in question, and A. pinguis from all 

 the other American species seen by him. 



92 A. angularis. Oblongus niger nitidus supra undique sparse subtiliter punctulatus, 

 thorace lateribus rotundato, angulis posticis obtusis non rotundatis, basi vix marginata, 

 utrinque oblique vix sinuata, lateribus punctatis, disco parce punctato, elytris profundius 

 crenato-striatis. Long. -26. Pic. Variat elytris piceis, pedibus rufo-piceis. 



Agrees with A. pinguis in being covered with a fine punctuation ; the clypeus is more 

 broadly emarginate, and the posterior angles of the thorax not at all rounded ; the basal 

 margin of the thorax is interrupted and indistinct. The $ has the thorax a little 

 wider than the elytra. Belongs also to Erichson's division D. 



13 A. consentaneus. Elongatus, rufo-testaeeus, elytris pallidioribus, capite thora- 

 ceque subtiliter sat dense punctatis, hoc lateribus parum rotundato angulis posticis ob- 

 tusis valde rotundatis, basi tenuiter marginata, elytris thorace non latioribus profunde 

 crenato-striatis. Long. -2. 



Clypeus margined, scarcely emarginate, frontal suture straight : the punctures of the 

 thorax are intermixed with a few very minute points. Belongs to division E, of Erich- 

 son. 



94 R. cribrosus. Piceus, opacus, thorace lateribus rectis, angulis posticis late emar- 

 ginatis, basi vix rotundata, grosse confertim cribrato, canaliculate, elytris antice suban- 

 gustatis, basi emarginatis, acute 10-costatis, sulcis uniseriatim leviter punctatis. Long. 

 16. 



Head convex, punctured, clypeus scarcely margined, oblique each side. I should 

 refer this species to Euparia, were not the posterior tibiae destitute of the rows of bris- 

 tles, and the external spur which distinguish that genus ; they have two scarcely dis- 

 cernible rudiments of teeth on the outer edge. The podex is entirely concealed by the 

 elytra. 



95 M. lacustris. Oblonga, convexa, postice subdilatata, nigra nitida, thorace trans- 

 verso, antice angustato, basi marginata, utrinque oblique subsinuata, angulis posticis 

 rotundatis, lateribus marginatis, anticeque impressis, sat dense grossius punctato, 

 elytris valde crenato-striatis, interstitiis convexis loevibus. Long. '18. 



Head convex, rough anteriorly with elevated granules, clypeus finely margined, widely 

 emarginate. There are also two species found on the Atlantic coast. 



