160 THE VOYAGE OF H.M.S. CHALLENGER. 



margin is armed with a small tooth within the internal orbital angle, two rostral in the 

 median line, behind which on the central dorsal ridge are successively three single 

 teeth, then two, then a single one anterior to the cervical fossa, posterior to which are 

 two on the margin and two a little behind, the rest of the ridge is smooth to the 

 posterior margin, on each side of which is a small sharp tooth. 

 The armature may be tabulated as — 



Marginal, ...... 5 — 3 — 7 



Dorsal crest, ...... 211-121 — 22- -2. 



The pleon is carinated, and the first two somites are armed with small anteriorly- 

 directed teeth ; the third and fourth with large and sharp ones ; the fifth has no tooth, 

 but a small cusp ; the sixth has a double baccated ridge that becomes confluent at the 

 posterior margin, and the telson is furnished with a small central carina and two small 

 ones on each side, a little posteriorly. 



The first pair of pereiopoda has the carpos armed at the distal or propodal extremity 

 with a small sharp tooth on the inner and outer angles; the meros is smooth on the inner 

 margin and armed on the outer with a single small tooth near the external distal or 

 carpal angle, and a second small solitary tooth, one-third distant from the ischial 

 joint. 



The posterior pair of pereiopoda is chelate, the pollex being shorter than the dactylos. 



Length (male), 50 mm. (2 in.). 



Habitat.— Station 174c, August 3, 1874; lat. 19° 7' 50" S., long. 178° 19' 35" E.; 

 off Kandavu Island; depth, 610 fathoms; bottom, coral mud; bottom temperature, 39° 

 One specimen. 



Compared with others this species is narrow across the carapace. The teeth on the 

 margins are slender and sharp ; that on the anterior angle particularly so. The several 

 divisions are clearly defined. The frontal margin is armed with four teeth between the 

 orbits, the two central are rostral, and the one on the inner angle of the orbit is within 

 the margin; posterior to the orbital notch is a row of three small sharp teeth situated 

 diagonally between it and the median line ; three other small teeth, two of which are not 

 shown in the figure, stand in a triangle, the posterior being on that part of the ridge 

 formed by the cervical fossa, where it bifurcates to form the median division, the second 

 stands on this branch, and the third is anterior and internal to it, Twelve teeth, includ- 

 ing the two anterior or rostral ones, traverse the central ridge of the carapace. The 

 branchial region is defined by a waved ridge, armed with small teeth. 



The first somite of the pleon is slightly narrower than the carapace ; the dorsal 

 portion is armed on the median line with a small sharp tooth directed forwards ; the 

 lateral extremity is armed with a tooth to the inner side of the peltecleis or shield-bolt 



