Coleopterological Notices. 123 



between the first and second joints is much less rigid and the motion 

 apparently perfectly free. 



In L. bicolor the metasternal process is wide, strongly rounded 

 throughout at apex, and does not extend to the anterior limits of 

 the coxae ; the mesosternum in front of it forms a perfectly flat 

 transverse piece, rather long, projecting beyond the coxae, with the 

 apex transversely truncate, and the surface bearing a transversely 

 arcuate row of robust recumbent spinose setae, projecting posteriorly, 

 the line of demarcation between it and the mesosternum extremely 

 fine. Behind the middle acetabula the mesosternum is very strongly 

 developed, the piece being posteriorly produced in a slender cusp, 

 extending almost to within one-third the length of the metasternum 

 of the posterior margin of the latter. The prosternal process is rather 

 wide, the posterior edge being free, acute, transversely truncate, and 

 bearing a series of four or five erect robust and prominent spinose 

 setae. 



On the upper surface the sutural bead is entirely obsolete, and 

 the single discal stria fine, close to the suture, and rather short. 

 The sculpture consists of very fine transverse strigilation which, 

 however, is not sufficiently fine and close to produce an opalescent 

 lustre. The punctures throughout are extremely minute and feeble, 

 not transversely crescentiform, and not more distinct at the sides, 

 in this respect being exactly similar to many species of Stilbus. 



No species of this Central American genus has yet occurred 

 within the United States. 



STILBUS Seid. 

 Olistherus^ Seid. ; — Eustilbu^ Sharp. 



Some of the structural characters distinguishing this genus have 

 been before indicated, and it is only necessary to state in general 

 that it differs from Olibrus in its short metasternal process, promi- 

 nent and tumid mesosternum, extension of the latter behind the 

 middle acetabula, in the form of the prosternal process which is here 

 furnished with a distinct free edge posteriorly, and armed with a 

 transverse series of stout setiform spinules, in the absence of a bead 

 along the elytral suture, in the form of the eleventh joint of the 



^ This is not, properly speaking, a pre-occupied name, Olistherus being to 

 some extent diflferent from Olisthaerus. 

 2 Biol. Cent.-Amer., II, Pt. 1, p. 253. 



