50 Natural History Bulletin. 



Trimioplectus, BrendeL 



TABLE OF THE SPECIES OF TRIMIOPLECTUS. 



Prothorax narrowing toward the base, to the width of the rather thick 

 neck. 



Vertex with the sulcus wanting or but faintly indicated; occipital 



foveze small, isolated. . . - - obsoletus n. sp. 



Vertex with deep fovese connected by a deep, arcuate, sulcus. 



arcuatus. 

 Prothorax slightly narrowed toward the base. 



Prothorax transverse, sides parallel in the middle; posterior angles 



broadiv rounded; head as wide as the prothorax. - ruficefs. 



Prothorax wider than long, sides convergent posteriorly; basal 



fovese smaller, and connected by a conspicuous sulcus. Head 



very much narrower than the prothorax - capitidum. 



T. OBSOLETUS, n. sp. Yellow, pubescence fine, sparse ; sur- 

 face impunctate or with obsolete punctures visible only under 

 a magnifying power exceeding sixty diameters; body convex. 

 Length 1.2 mm. Plate XL, Fig. 105. Plate XII., Fig. 123. 



Head, including the mouth, forming an equilateral triangle 

 with arcuate corners; vertex flat, with two round fovea? in a 

 line before the middle of the eye, the latter situated far down 

 on the sides; frontal margin straight with an obsolete trans- 

 versely impressed Hne between the small antennal tubercles, 

 not connected with the foveas; occiput sinuate. Aniennce 

 twice as long as the head, first and second joints thicker, 

 cylindrical; ninth transversely oval, as wide as the second; the 

 tenth larger, one-third wider than long; last joint twice as wide 

 as the tenth and as long as the three preceding together. 

 Prothorax very convex, very little longer than wide, sides 

 arcuate to the lateral foveee, thence straight to the base; the 

 transverse sulcus is one-fourth from the base, deep, straight, 

 connected with a triangular impression in the middle. Elytra 

 convex, sutural Hues straight, recurrent at the base, discal lines 

 recurrent for half the length, no intermediate basal punctures. 

 Abdomen convex, border moderate, basal dorsal segment 

 longer than any of the others; at the base is a transverse, 

 pubescent, linear, depression including one-half of the seg- 



