304 



BULLETIN r)4, UNITED STATES NATIONAL MUSEUM. 



DYNAMENE DILATATA Richardson. 



Dynamene dUatata Richardson, Proe. U. S. Nat. Mus., XXI, 1899, pp. 832-833; 

 Ann. Map;. Nat. Hist. (7), IV, 1899, pp. 175-176; American Naturalist, 

 XXXIV, 1900, ]). 223. 



Looillty. — Monterey Bay, California. 



Body oyal; surface vdvy granular; color yellow. 



Head rugose, with its anterior margin pro- 

 duced in a quadrangular process, having a small 

 median projection, rounded antero-lateral 

 angles and a thickened edge. First pair of an- 

 tenna? extend to the posterior margin of the 

 head, first two joints flattened and enlarged; 

 first joint oblong, second joint triangular, and 

 half as long as preceding joint; third joint 

 small, as long as second, but half as wide; 

 fiagellum six-jointed. Second pair of antennie 

 are but little longer than first pair and do not 

 reach the posterior margin of the first thoracic 

 segment. 



The thoracic segments are of equal length. 

 The epimera are square or oblong, with straight 

 lateral margins. 



The penultimate abdominal segment is short, 

 and crossed with suture lines. The terminal 

 segment is triangular with a small rounded 

 notch at the apex. There are three longitudinal ridges on the segment, 

 on(^ in the median line, and one on either side of it. The uropoda are 

 short, not reaching the extremity of the abdomen, and regularly 

 rounded. 



The legs are slender; the first two ])airs are covered with long hairs 

 and extend in an anterior direction, the other five pairs extend in a 

 posterior direction. 



The type and only specimen was collected by Mr. Heath at Monterey 

 Bay, California, at the surface. Cat. No. !i2.5()S, U.S.N.M. 



FiG.327.— Dynamene dil atata . 

 o, Head and first thoracic 



SEGMENT. X 13^. 6, DoRSAI 

 VIEW. X 10|. 



DYNAMENE BENEDICTI Richardson. 



Ihjnamene haiedirfi Kiciiakdsdn, Proe. U. 8. Nat. :\Iiis., XXI, 1S99, ]>. 834; Ann. 

 Mag. Nat. Hist. (7), IV, 1899, p. 177; American Naturalist, XXXIV, 1900, 

 p. 224. 



LocdJity. — Monterey Bay, California. 



Body oblong, oval; surface mimitely graiudar; color dark gray. 

 Head with small median point. Kyes situated post-laterally. First 

 pair of antenna^ extend to the middle of the first thoracic segment; 



