120 STALK-EYED CRUSTACEA. 
= 
Length (female adult), 96 mm.; length of carapace, 41 mm. ; breadth of 
carapace, 31 mm.; length of cheliped, 87 mm. (ischium, 16 mm., merus, 23 
mm., carpus, 9 mm., basal part of propodite, 15 mm., dactylus, 18 mm.). 
Station 3354. 322 fathoms. 1 male. 
“3402. 421 as 2 males, 1 fem. 
“« §=6©3403. 384 Ke 12 males, 14 fem. 
oe SA09 oa, es 1 fem. 
This species nearly resembles P. nanus (Smith), but may be easily distin- 
guished by the difference in number of spines on the median and sublateral 
carine of the carapace, by the presence of a spine on the antero-external 
angle of the first and second abdominal pleure, and by the greater number 
of spines on the merus, carpus, and propodite of the chelipeds. P. nanus is 
also described as having the posterior pair of thoracic legs chelate in the 
male. 
Compared with the types of P. agassizii (A. M. Edw.), the carapace of the 
present species is seen to be broader and fewer-spined on the margins; the 
first and second abdominal pleure are armed with an anterior lateral spine ; 
the rostral spine is double instead of being single ; the orbital sinus is broad 
and round at the bottom instead of being narrow and acute, ete. P. agas- 
sizii, like P. tanneri, has non-chelate posterior legs in the male. 
The branchial formula is as follows : — 
Somites VIII. Ix. ae Kol st eXGLT 29 eNO ERSTV Ze 
Pleurobranchize 0 0 0 1 iI i 1= 4 
Arthrobranchiz 0 0 2 2 2 2 OF — ao 
Podobranchize 0 0 1 1 1 1 O= 4 
Epipods 0 r i 1 1 1 O= (4+17) 
16+ (4+17) 
The epipods of the second, third, and fourth pairs of chelate appendages 
are very delicate in texture and about half as long as the podobranchize 
borne by the same appendages. The epipod of the first pair of chelate 
appendages is smaller than those back of it, while the one on the third 
maxilliped is reduced to a mere rudiment. 
