BEMBIDIIN.E 221 



the reflexicollis of Motschulsky, said to occur near New York City, 

 seems to be different, having the pronotum apparently more broadly 

 reflexed at the sides and the color testaceous. The dorsal elytral 

 fovese differ very much from those of Tachyta, being on the third 

 interval, very close to the third stria and they are very much less 

 widely separated, the anterior in fact but slightly before the middle. 

 The genus Mioptachys of Bates, is extremely close to Tachymenis, 

 having a similar conformation of the sides of the pronotum, and it 

 is my belief that it cannot be considered to be more than a subgen- 

 eric group of the genus, characterized by the narrow elongate form 

 of the body and deficient elytral striation. In the following table 

 I have described a species from Guatemala, which seems to be inter- 

 mediate between the normal flavicauda types of the genus and Miop- 

 tachys, having the slender form of the latter, with more restricted 

 striation than in flavicauda, though with the eyes not very small as 

 in Mioptachys but well developed, even more so than in flavicauda. 



Body oblong-oval, slightly convex, shining, piceous-black, the trans- 

 lucent sides of the prothorax testaceous, the elytra abruptly testa- 

 ceous in almost apical half and also sometimes more nubilously at 

 base; abdomen feebly testaceous at tip; legs pale flavo-testaceous; 

 integuments thick, the ground sculpture a very fine but not close 

 wavy transverse reticulation throughout; head small, scarcely three- 

 fifths as wide as the prothorax, with two small impressions at the 

 anterior margin of the front and an oblique ridge near each eye, 

 the latter rather small, slightly prominent; antennae testaceous, 

 three-fifths as long as the elytra; prothorax slightly less than one- 

 half wider than long, somewhat wider at base than at apex, the sides 

 parallel and feebly, subevenly arcuate, a little straighter behind the 

 middle, the angles slightly more than right, sharp; anterior impres- 

 sion subobsolete, the posterior sulciform, broadly arcuate, inter- 

 rupted at the middle, the stria coarse, attaining base but not apex; 

 elytra two-fifths to one-half longer than wide, two-fifths wider than 

 the prothorax, oblong, obtusely rounded in apical third, the humeri 

 broadly rounded, the seven striae evident, rather strong inwardly, 

 uneven or vaguely subpunctate; intervals each with a single series 

 of widely spaced and very small micro-setigerous punctures; foveae 

 minute, just before the middle and near apical fifth. Length 1.7- 

 1.75 mm.; width 0.7 mm. Atlantic to the Gulf and Lake regions 

 and westward to the Pacific. Abundant. [Tachymenis margini- 

 collis Mots.] flavicauda Say 



Body much narrower, shining, pale testaceous throughout above and 

 beneath, the elytra with a very faint central cloud; ground sculpture 

 nearly as in the preceding; head relatively larger, two-thirds as 

 wide as the prothorax, almost as in flavicauda in structure and in 

 the basal parts of the antenna? all but three joints missing in the 



