Boone, Crustacea, Cruise of "Alva," 1931 133 



telson; the inner blade is rather widely, evenly ovate, the outer 

 blade is similar, slightly wider, transversely articulated distally, 

 with an acute distal tooth at the termination of the outer lateral 

 margin. 



The great cheliped has the ischium small, laminate, one-third 

 as long as the merus; the merus is 2 millimeters long, fragile, 

 much slenderer than either finger, narrowly triquetral, being ex- 

 tremely compressed laterally and having a distinct concave excava- 

 tion on the dorsal distal margin and an acute subdistal tooth on the 

 inf erolateral margin ; the carpus is also very small, convex, distally 

 concavely cup-like on the dorsal half ; the propodus is very large, 

 as long as the ischium and merus considered together. The palm 

 has proximally on the outer distal and upper outer surfaces a deep 

 incision or groove, that is completely excavate on the proximal 

 end and continued on the upper half of the outer surface sinuate, 

 thrice recurved, becoming shallower distally and vanishing in an 

 upturned curve that becomes contiguous with the very deep trans- 

 verse channel which occurs across the upper surface, subdistal to 

 the end of the palm above the base of the upper finger and obliquely 

 situated and terminated definitely on the inner upper margin, 

 being closely adjacent to, but separated from, a wide deep groove 

 that distally runs down and forward obliquely to the base of the 

 inner edge of the upper finger; the upper end of this oblique por- 

 tion of the groove curves immediately below the before mentioned 

 transverse groove and thence curves downward, widening conspicu- 

 ously about midway the palm, thence curves downward almost to 

 the posterior margin, becoming weaker as it progresses and van- 

 ishing on the lower posterior margin at a point where the curved 

 proximal lower margin unites with the nearly straight lower 

 margin; anteriorly, about two-thirds of the length of the palm 

 from the base, the above defined groove is united with another 

 groove, which extends abruptly obliquely down to the base of the 

 lower finger and widens into a deep channel on the lower surface 

 of the finger, extending entirely across the lower surface and up 

 on the outer surface of the palm to a point midway the proximal 

 width of this finger ; running back from this transverse inferior 

 channel, on the lower and slightly outer surface, there is a not 

 quite straight linear groove that vanishes almost at the posterior 

 margin. The hinged finger is short, proximally broad on the outer 

 surface, with the upper lateral margin sinuate, and there is a small 



