86 bulletin: museum of compakative zoology. 



Labral margin deeply excavated at the middle, the black tooth projecting 

 into the incision short, obtuse, leaving most of the incision open. Surface of 

 head shining; puncta above sparse, not deep, but toward labral margin 

 becoming numerous. Antennal fossa basin-hke, closed in front as well as 

 behind by a ridge. Antennae very short as usual; attenuated distad, the 

 sixth article more slender than the more proximal ones, cyUndrical; seventh 

 article short, rounded, with four sensory cones. 



CoUum with anterior margin concave at the sides and bulging convexly 

 forward at the middle. Caudal margin between angles semicircular. Pro- 

 truding median region of anterior border set off by a fine transverse sulcu3, 

 but the latter short, not extending to the side regions. Surface smooth and 

 shining, weak puncta present in a series across anterior border but absent or 

 obsolete elsewhere. 



Second tergite very large; an anterior elevated border set off by a furrow 

 that is narrow and shallow in the middle region but widens and deepens down 

 the sides as usual; surface smooth and shining, not punctate. Surface of the 

 other tergites also smooth and shining and without puncta. 



Surface of last plate similar to that of the others. Lower border set off by 

 a very weak oblique depression. 



Tarsus of legs with a single spine above and well separated from the claw. 



Length (female), near 33 mm.; width, 16 mm. 



This species may be easily separated from those heretofore described 

 by the structure of the vulva. In this the basal division is large 

 with the two halves equal or very nearly so, not with the outer one 

 much the larger and overlapping the mesal. The distal piece has the 

 usual triangular form; its base obviously narrower than the width 

 of the basal division; its outer side more oblique than the mesal; 

 dark, strongly chitinous. 



215. Cyliosoma pachygon, sp. nov. 



Type.— M. C. Z. 4,697. Paratype.— M. C. Z. 4,698. Queens- 

 land: Cooktown, 1896 (A. G. Mayer). 



Color light chestnut of a somewhat ferruginous cast, the anterior plates 

 darker chestnut, the caudal borders of tergites black. Legs pale ferruginous. 

 Head hke the tergites but the collum darker, blackish. 



Median emargination of labrum subquadrate, the median tooth narrowly 

 conical, reacliing level of mouth of excision. Surface across and above 

 labrum and laterally toward eyes coarsely deeply punctate, but the middle 

 region smooth and shining with the puncta few and small. Antennal fur- 

 rows deep, pit-like, facing directly laterad toward the wing of the second 

 tergite. Antennae short, tapered distad as usual; the terminal article very 

 short, its sensory cones stout and contiguous or subcontiguous. 



