NO. 14 MILLIPEDS OF WEST INDIES AND GUIANA — LOOMIS 



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BEATADESMUS, n. gen. 



Type. — Beatadesmits utowani, n. sp. 



Diagnosis. — Although no males have been seen, the validity of this 

 genus seems well substantiated by the combination of characters rep- 

 resented by the very strong teeth of the lateral and posterior margins 

 of the segments near the middle of the body, and the different colora- 

 tion of the poriferous and nonporiferous segments. 



Description. — Body with the dorsum moderately convex, the sides 

 parallel to about segment 16. Posterior subsegments smooth above or 

 with one or two tiny tubercles on the surface of the keels. 



Fig. 16. — Beatadesmus utowani. a, segments 8 to 11, dorsal view; h, segments 17 

 to 20, dorsal view; c, first leg of segment 8, female. 



Head wider than the body, the cardo of the mandibles especially 

 prominent, long, subrectangular ; antennae long and slender, joints 

 2 to 6 inclusive of uniform thickness. 



First segment semicircular, with an erect seta on each side of the 

 middle close to the front margin. 



Ensuing segments with a sharp, prominent tooth at the anterior 

 corner of each keel from segment 2 to segment 16 (fig. 16, a), behind 

 which the tooth vanishes (fig. 16, h) ; on the middle segments the 

 tooth is larger and is produced outward and backward ; posterior 

 angles of the nonporiferous segments all strongly produced caudad, 

 especially in the midbody region ; on the poriferous segments the thick- 

 ened rim surrounding the pore occupies much of the lateral margin of 

 the keel and replaces the produced angle. Posterior margin of the 

 segments with a large tooth mesad of the posterior angle of each keel 

 and usually with a much smaller tooth mesad of it ; these teeth dis- 

 3 



