Occasional Papers of the Museum of Zoology 27 



Collum with lateral lobe on each side not at all inflexed, 

 subvertical, its anterior portion in part concealing the base of 

 cardo of mandible. Lower margin weakly convex, both ante- 

 rior and posterior corners rounded, the anterior one more 

 widely than the posterior. On each side three striae in addi- 

 tional marginal one which curves below the edge inferiorly, 

 the uppermost of these striae deepest as usual. See further 

 PI. 13, Fig. 88. 



In a typical segment of the middle region of the body the 

 suture is deep and wide, straight throughout or but weakly 

 excurved opposite the pore, and is crossed by longitudinal 

 ridges or ribs dividing it into a series of pits. Below the pore 

 most of these ribs continue across the metazonite as the lower 

 limiting ridges of the striae, which extend up to or nearly tc 

 the pore ;, shorter striae or simple sutural ribs in part alternate 

 with the principal striae and their limiting ridges. Pore nearly 

 one- fourth the distance from suture to caudal margin of meta- 

 zonite. Anterior region of prozonite with numerous regular 

 cross-striolations which anastamose at intervals, excepting the 

 most caudal one, or in part also the next to last, the striola- 

 tions finely beaded. Segment otherwise dorsally wholly 

 smooth excepting vague fine lines and punctae visible under 

 good magnification. Sternites nearly smooth, with only vague 

 cross-striolations finer than those of prozonite. 



Last tergite obtusely rounded behind, smooth. Anal valve 

 with mesal valve strongly elevated, each set oft" by a broad 

 furrow. Anal scale sharply set off by sulcus from its annulus, 

 the sulcus evenly turved ; caudal margin only slightly convexly 

 bowed out at middle. (See PI. 13, Fig. 89.) Last annulus 

 marked ventrally with strong cross-striations as shown in the 

 figure. 



