4 Mr. C. C. Babington's Descriptions 



CoLYMBETES (Rantus). Stejjh. Brit. Ent. (Mand.) 5, 393. 

 Rantus, Eschsch. 

 CoLYMBETES. Ericlis. Dytisc. 32. 

 A. Elytrorum apice oblique truncate, acuminate. 

 a. Thorace postice multo latiori. 

 1. (2.) C. reticulatus, Bab. 

 Oblongo-ovatus, supra flavicans, subtus niger, vertice et tho- 

 race antice posticeque nigris, elytris crebre nigro-reticulatis 

 striisque disci punctatis ; antennis pedibusque pallidis, tarsis 

 posticis nigris exceptis. (L. c. 5, lat. 2| lin.) 

 Oblong-ovate, yellow above. Head with the vertex broadly 

 black, antennae yellow. Thorax short, transverse, broadly emar- 

 ginate in front, with prominent acute angles, the sides oblique and 

 but sh'ghtly rounded, the posterior margin somewhat sinuated, the 

 angles obtuse and slightly rounded, smooth, with a series of im- 

 pressed dots on the anterior margin ; disk immaculate, the anterior 

 margin blackish, the posterior with a broad transverse black spot 

 attached to its centre. Scutellum triangular, black, with its apex 

 yellow. Elytra oblong, slightly dilated in the middle, the apex 

 obliquely truncate so as to form a sharp point at the suture, 

 slightly convex, vvith three lines of minute impressed dots upon 

 each, which are scarcely distinguishable in the female, yellow, 

 with the suture, apex, and numerous longitudinal lines connected 

 by reticulations, black, leaving the exterior margin and a slender 

 nearly continuous line next the suture yellow, tlie whole surface 

 minutely strigose in the female. Body beneath black, with the 

 abdomen somewhat fuscous. Legs yellow, the posterior tarsi 

 alone excepted, which are black. 

 Hab. Valparaiso, Chili. 



In this species, and all the others included in my Section A., 

 the claws of the anterior feet (PI, 1, fig. 2 a) are very large and 

 unequal in the males. One of them is broad and flat, and forming 

 an angle with the tarsi ; the other slender, setaceous, and about 

 a third part shorter. In the British species this structure occurs 

 in C notatus, Fab. and Steph. alone ; and even there it is not so 

 remarkable as in the species described in this paper. In all the 

 other British species of Rantus, these claws, although very long, 

 somewhat unequal in length, and forming an angle with the tarsi, 

 are yet of exactly the same thickness and form. The oblique 

 truncation of each elytron (PI. 1, fig. 2 b), thereby forming a point 

 at the suture, is a remarkable diflference between these insects, 

 and the allied European species. 



