252 Bulletin Vanderhilt Marine Museum, Vol. VII 



proportions of the carinae, especially the median longitudinal 

 flat carinae increasing in width and prominence on each succes- 

 sive somite posteriorly, as do also the transverse median ele- 

 vated areas on either side ; these on the pretelsonic somite form- 

 ing three approximate triangles, posteriorly directed, the lateral 

 pair being separated from the median one by a pair of triangu- 

 late depressions with apices directed anteriorly. The epimera of 

 the third somite are more triangulate than those of the second 

 with the anterolateral margin convex, crenulate or spinose, the 

 postlateral margin sinuate, distally concave, the two margins 

 converging to form a distal tooth with the apex directed pos- 

 teriorly. The fourth epimera are similar to the third pair but 

 a little smaller, with a more acute distal tooth ; the fifth pair are 

 similarly smaller than the fourth, while the epimeral area of the 

 sixth somite is different, being excavate on both anterior and 

 posterior margins, forming a median triangular process which 

 is distally rounded. The telson is subequal in length to or about 

 a millimeter longer than the sixth somite but distinctly narrower. 

 The telson is about one-fifth longer than its proximal width ; the 

 distal width is about one-third less than the proximal, the lateral 

 margins being flat, carina-like, terminating in a small, subdistal 

 tooth; the distal margin is evenly rounded between these teeth 

 and fringed with setae. The proximal area of the telson is ele- 

 vated in a wide, short, triangle medially and posterior to this 

 on either side is a very narrowed, elongated triangle, separated 

 on the outer side by a groove from the marginal carinae and with 

 the apex of this wedge-like triangle confluent with the lateral 

 carina at the base of the subdistal marginal tooth. The uropoda 

 are strong, with a short peduncle terminating in a small spine at 

 each the inner and outer distal angle. Both blades are wider dis- 

 tally, the inner one being as long as the telson and as wide dis- 

 tally with this margin truncate with the lateral angles rounded 

 and setigerous; a single, oblique, nearly median longitudinal 

 carina ; the outer blade exceeds the length of the inner one by the 

 articulated distal joint which has its setose distal margin more 

 convex ; there is also a strong, subdistal tooth on the lateral mar- 

 gin of the proximal article ; there is a strong longitudinal midrib 

 and a second, incomplete, longitudinal midrib between the median 

 rib and outer lateral margin. 



