36 CALIFORNIA ACADEMY OF SCIExNCES. 



bium, being absent in the latter genus. In Hefij^erohium 

 calt/ornicu'iii tLey are very large, slightly oval, strongly an- 

 nular and crater-like, occupying the entire summits of slight 

 elevations, and having their planes not exactly parallel to 

 the general surface but tilted very slightly forward, so that 

 the slope of the elevation is more prominent behind. Be- 

 tween them the surface is narrowly elevated or tumid in a 

 longitudinal direction, and from the middle of each arises a 

 very long erect seta from an annular median tubercle, which 

 corresponds to tJie cone of tlie crater. These most singular 

 structures are probably an additional distinctive feature of 

 Hesperobium. 



The genus Homseotarsus founded by Hochuth upon an 

 Armenian species, does not concern us at the present time, 

 as, although the maxillary palpi are apparently of like struc- 

 ture, it is, in almost all other res})Octs, entirely similar to 

 Cryptobium (Lac. Gen. Col. II, p. 90). 



II. 



In the first volume of this Bulletin, page 315, I stated that 

 the mandibles in Orus were quadridentate Avithin. This is 

 true only of the right mandible. Since the publication of the 

 paper referred to, I have examined the left mandible and 

 find it tridentate, the three teeth being small, ap])roximate 

 and situated almost exacth' in the middle of the inner margin; 

 the two basal ones are erect, slightly longer than wide, acute 

 and equal, the third being longer and more slender, acute 

 and rather strongly inclined toward the apex, the latter 

 being evenly and strongly arcuate, very acute and slender. 

 This coml)ination of four teeth in the right and three in the 

 left mandi])le is of frecjuent oc(;urrence in the portion of the 

 Panlcirini n(;ar and related to Lithocharis, where the man- 

 dibular characters apj)ear to lose the inq)ortauc(^ which they 

 possess in some other ])ortions of the group. Tlie al)n(u*mal 

 arrangement of the teeth in Orus therefor(% although it cannot 

 of itself be maintained as a generic cliaracter, still serves to 



