AMERICAN COLEOPTERA. 265 



BACTRIDIUM Lee. 



Head parallel behind the eyes, not at all constricted. Antennae 

 ten-jointed, terminal joint suddenly larger, ninth joint not wider 

 than the eighth. Intercoxal process rather broad, truncate in front. 

 Elytra with rows of punctures. First ventral segment with distinct 

 coxal lines. 



Three species occur in our fauna, two from the Atlantic region 

 and one from California, others are known to me from Mexico 

 {adusfum Reitter), and Rio, (^Fryi n, sp.). 



They may be known as follows : 



Thorax merely flattened or with linear impressions. 



Sides of elytra closely finely striate epfaippigernin Guer. 



Sides of elytra smooth or sparsely punctate. 



Body beneath and abdomen scarcely punctured. 



Thorax merely flattened; elytra rufous, tip and sides piceous. 



Striatum Lee. 

 (Thorax depressed and with a crescentic impression; elytra yellowish. 



Fryi n. sp.) 

 Body beneath and abdomen rather coarsely punctured. 

 Color piceous, thorax and elytra scarcely depressed. ..striolatum Rttr. 

 Thorax at middle broadly concave. 



Elytra with a broad, vague longitudinal impression eavicolle n. sp. 



Crine Pasc, Journ. of Ent. ii, 1863, p. 29, does not diiFer from 

 Bactridium, his species is however quite different from Fryi^ which 

 is from the same region. 



B. eplaippigeruiu Guer., (HMzoph.), Icon. Eegne Anim. p. 190, pi. 41, 

 fig. 1; erythropterum Mels., Proc. Acad, ii, p. 109; nanum Erich., Germ. Zeitschr. 

 iv, p. 360. — Piceous, shining, depressed, elytra rufous, sides and tip darker, an- 

 tennae and legs rufous. Head rather coarsely and densely punctured. Thorax 

 slightly wider than long, sides feebly arcuate and somewhat narrowed to base, 

 margin posteriorly bidenticulate, disc flattened and with a vague median im- 

 pression limited on each side and posteriorly with a very indistinct margin, 

 surface sparsely punctured at middle, much more densely at the sides. Elytra 

 slightly wider than the thorax, finely striate, strise at the sides finer and 

 approximate, those of the disc with fine, rather closely placed punctures. 

 Body beneath sparsely jjunetured. Abdomen coarsely punctured, the last 

 segment densely and rugulose, first segment with distinct coxal lines attaining 

 the hind margin. Length .08 inch; 2 mm. 



This species is easily distinguished from every other in our fauna 

 by the densely striate sides of the elytra. 



Occurs from New Tork to Missouri and Louisiana. 



B. striatum Lee, [Monotoma), Proc. Acad. 1S5S, p. 65. — Elongate, de- 

 pressed, rufous, shining. Head sparsely punctate. Thorax as wide as long, 

 sides in front slightly arcuate posteriorly, straight and gradually convergent 

 posteriorly, hind angles rounded, margin posteriorly obsoletely bidentate, disc 



TRANS. AMER. ENT. SOC. Til. (34) JUNE, 1879. 



