46 Mr. H. W. Bates on 



articulo primo grosse punctato ; thorace quadrato, 

 supi'a scabrosOj in medio elevationibus indistinctis 

 duabus Iffivioribus ; elytris vix nitidis, passim crebre 

 minus profunde punctatis, angulis suturalibus spino- 

 sis ; sternis omnibus grosse punctatis, pedibus anticis 

 denticulatisj tarsis piceo-rufis ; ventris segmentis sin- 

 gulis valde convexis. 



Long. (^ (mand. incl.) 2 unc. 4 lin. 



Very similar in shape and sculpture to M. nohilis, 

 Thoms., from Venezuela, tlie thorax being almost exactly 

 of the same outline and surface ; it differs in being 

 entirely black, in the absence of fulvous hairs from the 

 epistome, and in the great thickness of the mandibles. 

 These organs are much shorter than the head, and are 

 abruptly dilated externally, the apex of each ending in 

 a long acute point, and the inner edge about the middle 

 being advanced, and ai-med with four short broad teeth, 

 nearly as in Mallodon spinibarhis. The elytra have a 

 marked convexity from base to apex. 



I met with only one example of this species, at Ega^ 

 cast up on a sandy beach, after a storm. 



Genus Mallodon. 

 Serville; Lacord. Genera, viii. p. 125. 



1. Mallodon spinibarhis. 

 Lin. Mus. Lud. Ulr. p. 67. 



M. piceo-niger, elytris castaneis, vel omnino fusco- 

 niger, capite grosse punctato, genis sub mandibulis 

 prolongatis acutis ; thorace plagis politis septem, in- 

 terstitiis in c? subtiliter crebre punctatis, in ? 

 scabrosis ; elytris subtilissime sparsim punctatis ; 

 processu prosternali piano, c? crebre punctato, ? 

 glabro. 



A widely-distributed insect, found sometimes in great 

 numbers, under the loose bark of felled trees ; it is very 

 unstable in the outline of the thorax in both sexes, but it 

 may always be distinguished from the nearest allied 

 species by the angles of the cheeks below the mandibles 

 forming a simple point, instead of being bifid, I have 

 specimens from Mexico, Cayenne, and Rio Janeiro, as 

 well as from the Amazons. 



