On Aquatic Carnivorous Coleoptera or Dytiscidce. 761 



1228. Colymbetes (Ilybius) fraterculus, Lee, Proc. Ac. Phil. 1862, p. 521. North America. 



" Base of thorax broadly rounded ; brownish-black, slightly bronzed, oval, slightly dilated at the 

 middle, not less obtuse behind ; thorax with the sides nearly sti'aight ; elytra with the anterior pale spot 

 very small, the hind one wanting ; lines of punctures visible only behind the middle. 42. North Eed 

 Eiver." 



1229. Colymbetes goedeli. Villa, Col. Eur. dupl. 1833, p. 33. Italy. 



" Ovatus, niger, subdepressus ; pedibus elytrisque piceis ; thoracis elytrorumque margine exteriore 

 Have." 



TJiis may I think be allowed to be forgotten in future. — D. S. 



1230. Colymbetes gutticollis. Say, Ti-. Am. Phil. Soc. IV, p. 442. Mexico. 



" Thorax yellowish with four black spots ; head black, anteriorly and band of vertex yellow. Head 

 black ; a transverse yellowish band between the nearest points of the eyes ; a dilated yellowish triangle 

 occupying all the anterior part of the head, tlie apex being at the middle of the face ; antennae and 

 palpi honey-yellow, dusky at theii- tips; thorax honey-yellow, anterior margin blackish; posterior 

 margin dusky ; four large black spots in a transverse series, the two intermediate ones nearer together ; 

 elytra honey-yellow with minute black points more or less crowded so as to give a dusky, sometimes 

 almost blackish appearance ; lateral margin destitute of black punctures, but with a black line on the 

 posterior curvature ; at base, particularly the humeral base, destitute of the black punctures ; three 

 regular series of small black dots ; beneath black ; pectus, feet and epipleurse yellowish. Length, over 

 two-fifths of an inch." 



" Taken in the river beyond Vera Cruz." 



"It is about the size of the C adspersus, Fab., which it considerably resembles if we except the thoracic 

 black dots." 



This is probably near if not actually identical with C. binotatus (No. 935) ; the description in 

 several points does not apply to that species very well. — D. S. 



1231. Colymbetes impressus, Zubk., Bull. Mosc, VI, 1833, p. 317. Turcomania. 



" Long. 3 lig., larg. 1^ lig. II est brim avec les bords de la tete, du corselet et dea elytres un peu ferru- 

 gineux. Le corselet a une impression bien marquee au milieu, pr^s du bord posterieur. Les Elytres 

 paraissent lisses, mais avec une forte loupe on voit qu'ils sont couvex-ts de petits points tres rapproch^s. 

 Chaque elytre a le long de la suture une serie de points enfonces, rapproch6s, inegaux. Le dessous du 

 corps est noir ; les pieds sont ferrugineux. 



" Turcomania." 



1232. Colymbetes inaequalis, Horn, Tr. Am. Ent. Soc, 1871, p. 330. North America. 



" Elongate oval, broader behind the middle. Head black with vertical rufous spot, and anterior 

 margin pale yellow, very finely and densely punctured. Thorax yellowish or brownish with median 

 transverse band and narrow margin at middle of base black, surface intricately and confluently lined and 

 in the intervals punctured, lines obsolete at margin which is densely and finely punctured with a few 

 coarser punctures intermixed. Elytra brownish, sometimes paler, margin paler than disc ; surface 

 sculptured with transverse lines more deeply graven at the basal two thirds, in which region the surface 

 is subopaque from the intervals between the lines being scabrous ; apical third more shining. Body 

 beneath black shining, surface finely transversely strigose, strigse becoming longitudinal at the first two 

 abdominal segments and at the sides of the others, and at the middle of the segments the lines are nearly 



