178 ]\Iiss H. Richardson on the hopods of the 



24. Dynamene glabra^ sp. ii. 



Body oval ; surface smooth. 



Head small ; eyes situated post-laterally. First pair of 

 antennae extend to the eye; first joint oblong ; second joint 

 short, half as long as first ; flagellum contains six articles. 

 Second pair of antennae extend to the 

 posterior margin of the first thoracic 

 segment ; flagellum contains about 

 ten articles. 



Thoracic segments are subequal ; 

 the first is a little longer than any 

 of the others. 



The penultimate abdominal seg- 

 ment consists of several coalesced ^^,,„,„,„,^;^j,^ ^^g, 

 segments, as indicated by the suture- Abdomen aud last two 

 lines. The terminal segment is tri- thoracic segments, 

 angular, with a small median excava- 

 tion at its extremity. 'J he lower part of this segment is 

 quite flat, the slope being gradual from the convex upper 

 }iart or base of segment to the extremity. The inner branch 

 of the uropoda is large and rounded posteriorly ; the outer 

 branch is small, though similar in shape, and is much shorter 

 than the inner branch. 



A number of specimens were collected by Mr. Heath at 

 Monterey Bay, California, at the surface. 



Type. No. 22571, U.8. N. M. 



13. Sph^eoaia, Latrcille. 

 Analytical Key to the Species o/ tSph^roma. 



Body ^Yidening gradually from bead 

 backwards. Thorax transversely 

 ridged and provided \vith three longi- 

 tudinal rows of small tubercles. 

 Branches of the uropoda very large, 

 expanded 25. S. amplicauda, Stimpson. 



. Body not increasing in width. Sur- 

 face of tliorax pmootli. Branches of 

 the ur(»poda not expanded. 



h. Extremity of abdomen produced in a 



rhomboid process 26. iS". rhomburum, sp. n. 



i'. Extremity of abdomen not produced. 



c. Surface of abdomen tubercular , . 27. •S'. octoncmn, sp. n. 

 c'. Surface of abdomen smooth .... 28. 5. oregontnsis, Dana, 



