ABT. 19 KEVISION OF THE USECHINI BLAISDELL 6 



tubercle on summit of the apical declivity (fig. 1, A) ; third costa entire 

 and bituberculate posteriorly — at summit and middle of the declivity, 

 ending in the apical tumescence; ninth costa submarginal and entire, 

 continous with the reflexed humeral margin anteriorly and ending in 

 the apical tumescence posteriorly, being distinctly tuberculate at 

 middle of the apical declivity laterally. Interval four not in the 

 least convex, sixth and eighth nearly or quite obUterated, all irregular 

 from the two adjoining series of coarse punctures; the sutural 

 interval becomes distinctly convex at sides of the scutellar depres- 

 sion and attains the basal margin independantly of the third, the 

 two expanding on the basal edge and forming a prominent margin. 

 Second and third series of punctures very deep and perforate in the 

 central and basal portion of the disk, each puncture bounded later- 

 ally by a small decurved and overhanging tubercle, punctures usually 

 fille^ with detritus. Intrahumeral impressions asperately sculptured. 

 Scutellar depression scarcely declivous anteriorly, scutellum narrowly 

 triangular, very small, feebly or not at all entering between the elytra. 



Abdomen with the ventral sutures deeply impressed, apical and basal 

 margins abrupt and more or less crenulate ; segments 1,2, and 3 almost 

 impunctate laterally. Lateral margins of the segments thick, especi- 

 ally that of the fifth at apex; the fifth rather deeply impressed laterally 

 and subcarinate on the median line. Under surface of the body very 

 coarsely punctate. Tarsi short and slender; claws small and slender. 



Male. — Abdomen very feebly impressed in middle third of segments 

 1, 2, 3. Surface of fifth segment more strongly impressed laterally, 

 less convex, the impression divided by a median convexity. Posterior 

 margin of the anterior coxal cavities more or less narrowly open. 



Female. — Abdomen evenly convex. Fifth ventral less broadly 

 impressed and more in the form of a coarse submarginal groove; 

 posterolateral triangular area of the first segment impunctate. Pos- 

 terior margin of the anterior coxal cavities slightly more widely open. 



Measurements. — Length 3.1-5.5 mm.; width 1.4-2.1 mm. 



Distribution. — CaHfornia (Duncan Mills, Sonoma County, July 16, 

 1908; Lagunitas, Marin County, September 22, 1912). 



Habitat. — On fungus and under moldy bark of dead trees where 

 slightly humid. 



In addition it may be noted that in lacerta the pronotal discal 

 impression behind each antennal fossa is impunctate, that the costate 

 seventh elytral interval ends at basal fifth behind the humeral 

 impression. The sutural rows of punctures attain the margin 

 between the apical tumescences, the latter being mainly in fine with 

 the costate third interval ; the costate basal parascutellar portion of 

 the sutural interval curves slightly outward around the scutellar 

 impression, the latter rather cavernously unipunctate each side 

 beneath the costae. 



