Boone, Crustacea, Cruise of "Alva," 1931 221 



Thoimx: The first segment is not produced around the head; 

 the first, third, fourth, fifth, and sixth segments subequal in 

 length, each being a trifle longer than the second segment, which 

 is a line wider than the seventh segment. The epimera of the 

 second, third, fourth, fifth and sixth segments extend across the 

 entire lateral margin of the related segment, and those of the 

 second and third segments have the outer postlateral angle 

 rounded, while that of the second segment is more than that of 

 the third segment, which is bluntly rounded ; while the postlateral 

 angles of the fourth, fifth, sixth and seventh segments are in- 

 creasingly acute and produced, that of the last thoracic segment ex- 

 tending almost to the posterior margin of the second abdominal 

 segment. Each epimera has an oblique carina extending across 

 the dorsal surface, in addition to the carinate anterior margin 

 there is also a light carina along the outer margins of the thoracic 

 segments ; on the first, second and third segments it extends across 

 the entire segment, but on the fourth to seventh segments, in- 

 clusive, the carina runs obliquely inward. 



Abdomen: The first abdominal segment is almost entirely con- 

 cealed beneath the last thoracic segment; the second, third and 

 fourth segments are subequal, punctate and hirsute; the fifth 

 segment is slightly longer in the median line than the fourth seg- 

 ment, but is also narrower, having the postlateral parts concealed 

 by the closely appressed fourth segment ; the telson is an almost 

 equilateral triangle, with the apex acute, the dorsal surface finely 

 hirsute, the margins setose. The uropoda have the peduncle 

 strong, produced obliquely, the inner distal angle acute, extending 

 nearly half-way the length of the inner blade. The outer blade 

 is narrowly lobate, wider proximally, tapered distally, a little 

 shorter than the inner blade, with the margins crenulate and se- 

 tose. The inner blade is nearly one and one-half times as wide as 

 the outer, with the outer margin nearly straight, the inner mar- 

 gin shorter and decidedly more convex, obscurely truncated dis- 

 tally, giving the blade an asymmetrical contour ; the margins are 

 crenulate, setose. The rhipidura is longer than the telson; the 

 shorter inner blade being about 1 mm. longer than the telson, 

 while the outer blade is about 2 mm. longer. The first pair of 

 pleopoda have the outer branch a little shorter and wider than the 

 narrowly ovate inner blade, which has its sides subparallel. 



Legs: The first three pairs of legs are prehensile, fairly strong, 



