56 H. J. HANSEN. 



Group III. 



11. Scntigerella crassicornis, n. sp. PI. 4^ figs. 4 a — 4r; 

 PI. 5, figs. 1 a— 1 g. 



Material. — Eight well-preserved specimens, five of wliicli 

 are adult. 



Head. — Seen from above (fig. 1 a) it is moderately narrow, 

 scarcely angular on the sides, and tlie usual lateral seta is as 

 long as the basal antenna! joint. The central rod is not 

 visible anteriorly, terminating apparently in front of the 

 middle in rudiments of two branches; posteriorly it is con- 

 nected with the vertex of a triangle situated at the hind 

 margin of the head ; the sides of this triangle are concave, 

 consisting of rather feeble oblique rods. 



Antennae. — The number of joints varies from twenty-seven 

 to thirty-one. In one case twenty-one joints have been 

 observed in an animal with twelve pairs of legs. The joints 

 from the second to the ninth or tenth (fig. 4 a), and especially 

 the fifth to the eighth, are considerably thickened in the 

 adults — to a less degree in immature specimens, — and on the 

 inner side (fig. 4 ?>) two or three of the setas in tlie central 

 whorl are strongly elongate, the longest three to four times 

 longer than the outer seta), and nearly vertical on the 

 longitudinal axis of the antennte. The second whorl begins 

 below on the eighth to the tenth joint, but is quite absent on 

 the upper side of all joiuts (fig. 1 h). The joints, with excep- 

 tion of seven or eight proximal ones, have a small, conical, 

 robust rod on the upper side in front of the central whorl. 

 The tcrmiual joint with a rather large and long-stalked 

 striped organ inserted ou a lower protuberance, one or two 

 small and short-stalked striped organs, and finally a large 

 wart-like protuberance, on which I have never found any 

 organ. 



Scuta. — The second scutum (fig. 1 c) with the posterior 



