TENEBRIONIDAE 199 



Legs rather long, moderately strongly and densely sculptured. 



Measurements. Length, 25 mm. ; width, 10 mm. 



Holotype, female, as described above, in the collection of the Cali- 

 fornia Academy of Sciences. An allotype in my own collection. 



Type locality and habitat. San Benito Island, off the coast of Lower 

 California. Collected July 15, 1905, by F. X. Williams, while with the 

 Galapagos Expedition. 



Pectoralis is distinct by its parallel form, punctuation of under sur- 

 face and other characters ; apparently not identical with any described in 

 the Biologia. 



In spiculifera Lee. the mesosternum is almost declivous anteriorly, in 

 pectoralis it is strongly so, as it is in dulzurae described below. The meso- 

 sternum is vertical and emarginate anteriorly in asperata Horn, angularis 

 Horn, variolosa Horn, seriata Lee. and slightly declivous in muricata Lee. 

 Pectoralis somewhat resembles spiculifera, with muricata next in order. 

 Spiculifera is a larger and broader species, with the abdomen almost 

 impunctate and the legs more sparsely and less coarsely sculptured. In 

 spiculifera, also, the mentum is transversely cordate, apex feebly emar- 

 ginate, surface slightly convex and coarsely punctate, with the antennae 

 less slender and parallel, with the ninth and tenth joints triangular, the 

 eleventh longer. In pectoralis the mentum is cordate, relatively larger, 

 somewhat concave, more strongly emarginate at apex, feebly subcarinate 

 along the median line, longitudinally and not strongly impressed laterally, 

 coarsely punctate and more scabrous. 



Centrioptera dulzurae, new species. Form elongate-oblong, similar 

 to muricata. Color dull black ; pronotum sculptureless, elytra with muri- 

 cate tubercles laterally and on apical declivity. Mesosternum declivous 

 anteriorly ; abdomen smooth with a few scattered punctures. 



Head slightly convex, fronto-epistomal margin arcuate, somewhat 

 oblique laterally ; surface punctate, punctures irregularly and very sparsely 

 placed, finer in the central area. Antennae rather short with joints of 

 equal width, joints four to eight suboblong, ninth triangular, tenth sub- 

 quadrate, eleventh short pointed ovate. Mentum feebly convex, more 

 oval than cordate, slightly transverse, apical emargination not strong; 

 surface narrowly impunctate at apex, elsewhere rather coarsely and closely 

 punctured, somewhat longitudinally impressed laterally. 



Pronotum rather more than a fourth wider than long ; sides broadly 

 and evenly arcuate anteriorly, somewhat convergent and broadly sinuate 

 posteriorly to the basal angles which are rectangular: apex truncate 

 between the strong, anteriorly prominent and acute angles ; base truncate ; 

 disk evenly and very moderately convex, a little less so basally, sculpture- 



