120 STALK-EYED CRUSTACEA. 



Length (female adult), 90 nun. ; 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., dactyhis, 18 mm.). 



Station 3354. 322 fathoms. 1 male. 



" 3402. 421 " 2 males, 1 fem. 



" 3403. 384 " 12 males, 14 fem. 

 " 3409. 327 " 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 

 carina) of the carapace, by the presence of a spine on the antero-external 

 angle of the first and second abdominal pleurte, 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 pleurte 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, etc. P. agas- 

 sizii, like P. tamieri, has non-chelate posterior legs in the male. 



The branchial formula is as follows : — 



The epipods of the second, third, an'd fourth pairs of chelate appendages 

 are very delicate in texture and about half as long as the i^odobranchiae 

 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. 



