Sept., I9I7-] Fall: New Dytiscid^. 179 



fluent at base, again in a broad median indented fascia, and finally to form 

 a transverse subapical blotch, leaving a subbasal and a postmedian transverse 

 series of elongate spots or streaks, the side margin basally and the apex pale. 

 Metasternum very coarsely not closely punctate ; coxal plates similarly coarsely 

 punctate basally, becoming gradually much more finely and sparsely so postero- 

 externally ; first and second ventral segments strongly but sparsely punctate 

 except at sides of latter, the following segments very finely sparsely punctulate. 

 Length 2.95 to 3.1 mm.; width 1.48 to 1.55 mm. 



Virginia (Ash Grove), 4 c?'s, 3 ?'s, sent by Mr. Sherman. The 

 type is a male. 



The sexes are barely distinguishable by the very slightly stouter 

 and just perceptibly sinuate front claws of the male. There is no 

 apparent difference in surface luster, and the front tarsi are rather 

 narrowly and equally dilated in both sexes. 



Mr. Sherman writes of this species : " Like specimens in the Cam- 

 bridge Museum labeled ' tigrinum Zimm. MS.' Has been taken in 

 running brooks with blanchardi Sherm. and striatopimctatus Melsh, 

 but less common than either of these species." 



Oddly enough, this little species is probably more nearly related 

 to these same two species which Mr. Sherman says occur with it, 

 than to any others in our fauna. That the species described by Sharp 

 as H. vitiosus Lee. is not the true vitiosus was discovered, and re- 

 ferred to in notes taken by the writer in July, 1900, while making 

 comparisons with some of the Leconte types at the Cambridge Mu- 

 seum. Mr. Sherman has recently^ proposed the name blanchardi for 

 this species. 



It is, of the two species mentioned, most nearly allied to tigrinus. 

 It is slightly larger and more depressed, the form more ovate, i. c, 

 more pointed behind, with the point of greatest width more nearly 

 at the base of the elytra; the markings more obscure as a rule, the 

 punctures of the thorax more uniform in size, and those of the elytra 

 less conspicuously diminishing in size apically; the punctuation of the 

 metasternum and coxal plates is obviously finer than in tigrinus. 

 Blanchardi has been taken plentifully at Tyngsboro, Mass., by the late 

 Frederick Blanchard and myself, and is known to me also from Conn., 

 N. J., Pa., Va., and Ala. 



1 Jour. New York Ent. Soc, XXI (1913), p. 52. 



