96 bulletin: museum of comparative zoology, 



Collum of usual general form; more than twice as wide as head; in length 

 about equal to the two succeeding somites. 



Tergites extending on each side below level of pleurites, with dorsum 

 strongly arched. Caudal margin of tergites below on each side essentially 

 straight, the caudoventral corner rectangular, sUghtly narrowly rounded. 

 Caudal edge of pleurite beginning ectally in front of caudal corner of tergite 

 and running caudad of mesad, straight, inner caudal corner a Uttle rounded, 

 mesal margin straight, a httle oblique. 



Somites not constricted, the prozonites depressed only a Uttle anteriorly. 

 Body proportionately broad and heavy. Hairs moderate in length, not stout, 

 uniform. 



Number of segments (female type), fifty-nine. 



Length, to near 15 mm.; width, near 1.2 mm. 



257. SiPHONOTUs socius, sp. nov. 



Type.— M. C. Z. 4,962. Paratype.— M. C. Z. 4,963. Solomons: 

 Fulakora (W. M. Mann). 



General color fulvous of a weak ferruginous cast. Antennae dark, purplish 

 black, especially distally. 



Head similar to that of preceding species but in side view more pointed 

 below with curve of face weakly indented at beginning of frontal region below 

 which more strongly convex than in the other species, in upper clypeal region 

 somewhat incurving and then convex above lower end. Differing from that 

 species obviously in the antennae which are smaller, being both shorter and 

 more slender and much more nearly cyHndrical with the sixth article more 

 strongly narrowed distad and all articles shorter. 



Collum differs in having lower posterior angle more acute, the lateral 

 margin in front of it weakly widely concave. 



The transverse suture of segments in general more sharply and deeply 

 impressed. Body as a whole somewhat slender and more strongly narrowed 

 cephalad. 



Number of segments from near fifty-six to eighty-two. 



Length, to 13 or 14 mm. 



This form is very close to the preceding species from which it is 

 separated with some hesitation, though when the two are placed 

 together it may be distinguished by differences in color, robustness, 

 and especially in form of antennae and face. Unfortunately no males 

 are available for comparison. 



