o BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



DESCRIPTION. Dorsum yellowish to chestnut brown, the pos- 

 terior segments darker as is also frequently the first one. Head, to- 

 gether with the prehensors and prosternum, brownish red; the head 

 frequently darker, blackish, along the frontal suture. Antennae 

 yellowish red with the yellow sometimes dominating; mostly darker 

 proximally than distally. Legs dusky yellow or brownish yellow, 

 sometimes a little reddish distally; posterior pairs darker. Venter 

 dusky brownish yellow with the posterior segments darker, brownish 

 or, in some, of reddish caste. 



Slender; but little attenuated cephalad from eighth segment; dis- 

 tinctly attenuated caudad from tenth segment as usual; 8 to 8.5 times 

 longer than width of tenth plate. Body in general sparsely hairy, 

 the hairs being more numerous on the legs ; antennae densely clothed, 

 the hairs more numerous distad. 



Head subcordate; equal in length and breadth or very nearly so. 

 Rugose; commonly two or three pairs of longitudinal furrows, one 

 pair diverging cephalad with others on caudolateral portion. Punc- 

 tae rather coarse and scattered. 



Prosternum considerably produced cephalad, attaining the meso- 

 distal end of prefemur; anterior edge narrow, at middle narrowly 

 incurved. Teeth 3+3, of which the outer on each side is at the edge 

 of anterior margin, commonly much smaller than others and spines- 

 cent (Plate 1, fig. 7). Prosternum not quite 1.75 times wider than its 

 greatest length. 



Antennae short, about 2.4 times longer than the head while the body 

 is about 3.5 times their length. (In small specimens often relatively 

 longer, ratio to body length being sometimes as much as 1 : 2.7). Sub- 

 moniliform. Nearly always composed of 25 articles, very rarely of 

 28 or 29, or, in the other direction, of 24. First two articles long, the 

 second being clearly the longer as usual; all others decidedly shorter; 

 the tenth and eleventh articles uniformly shorter than the adjacent 

 ones and in most the third and fourth articles also shortened, though 

 frequently the fourth is shortened without the third as may also be 

 the eleventh without the tenth. 



Dorsal plates well arched; in adults mostly with a rather wide 

 longitudinal furrow each side of the middle; the lower lateral and 

 caudal borders set off by sulci paralleling the margins. Sometimes a 

 very shallow median longitudinal furrow may be detected. First, 

 third, fifth, eighth, tenth, twelfth, and fourteenth dorsal plates with 

 caudal corners rounded and with a caudal margin mesally incurved. 

 Seventh plate with caudal margin mesally straight, not at all incurved ; 



