648 FAMILY IV. SCOLYTIDyE. 



with further detail, but still regarded with doubt by Chittenden, 

 who states that this species passes its entire existence from egg 

 to imago in the wood, never under the bark, the imago probably 

 maturing in August, but gnawing its way out to the light only in 

 April following. It is extremely abundant in redbud, especially 

 in smaller limbs that have become dry and sapless and are easily 

 crumbled between one's fingers. 



M. aculeatus Lee. is a synonym of suturalis. It was based on a speci- 

 men in which the pubescence of elytra was well preserved, "clothed with 

 short, suberect yellowish hairs which are slightly clavate." (LeConte.) 

 Chittenden states the synonymy on the authority of Schwarz. 



1045 (9138). MICBACIS NAN TLA Lee., 1876, 368. 



Differs by the eyes being contiguous beneath, the gular space be- 

 tween the eyes of suturalis being absent and the eyes themselves more 

 coarsely granulated. Smaller and narrower than the other species, brown, 

 elytra somewhat shining, with numerous rows of short, pale bristles, 

 sutural prolongation less prominent. Length 1.7 mm. 



Dunedin and Haulover, Fla. ; March 4. Occurs on Myr'u-a. 



1046 (9141). MICRACIS RUDIS Lee., 1876, 368. 



Cylindrical. Nearly black, rather shining, antennae reddish-brown. 

 First joint of club with tuft of hairs near tip. Head very deeply exca- 

 vated; eyes widely distant above. Thorax somewhat longer than wide, 

 broadly rounded in front, sides parallel behind, surface sparsely granu- 

 late behind, rough with numerous tubercles in front. Elytra scarcely 

 pubescent, rugosely punctured, punctures large, arranged in approximate 

 rows; intervals rough with small acute tubercles on the declivity which 

 is convex except near the concave tip, sutural point well developed. 

 Tibiae feebly toothed on outer edge, fringed with long hair, front pair as 

 broad at base as tip. Length 2.5 mm. 



Vermilliou and Marion counties, Ind., rare; Jan. 1 June 15. 

 Described from Detroit, Mich.; District of Columbia in willow; 

 southwestern Pennsylvania. Food plants, hackberry, locust and 

 hickory. 



1047 (9140). MICBACIS OPACICOIXIS Lee., 1878, 625. 



Slender, cylindrical. Dirty testaceous, thorax darker, thinly sprin- 

 kled with very small ochreous scales. Club of antennae wltn broadly 

 curved sutures, scape (male) fringed with very long hair. Eyes extend- 

 ing to under surface of head, not widely but distinctly separated beneath. 

 Thorax opaque, indistinctly punctulate. Elytra shining, punctured in rows; 

 intervals with rows of very short stout bristles. Length 1.7 mm. 



