oltained during the Cruise of the ' Oceana.'' 419 



Pastph(Ba. The clielipeds of the first pair are shorter than 

 the second, the merus has a few setse on its lower edge, and 

 the palm is but little longer than the fingers. The second 

 pair have the merus armed with five spines on its lower edge 

 and the chela is more slender and longer by one half than 

 that of the first pair. The fourth pair of legs are a little 

 less and the fifth pair a little more than one half the length 

 of the third pair. 



The gills comprise five pleurobranchs corresponding to 

 the five legs, a minute papilliform epipod on the third 

 maxilliped, and four simple processes representing arthro- 

 branchs attached to the third maxillipsd and the first three 

 legs, the most posterior being exceedingly minute. It is 

 very probable that this rudimentary condition of the arthro- 

 branchs is an indication of immaturity, for I find that in 

 specimens of P. sivado of 20 millim. in length [i. e., not more 

 than one third of the adult size) the three arthrobranehs, 

 which in the adult are well-developed gills *, are represented 

 by simple papillae, while of the fifth pleurobranch, rudimen- 

 tary in the adult, no trace can be detected. Although these 

 specimens of P. sivado have assumed in most other respects 

 the characters of the adult, there is no certainty that such is 

 the case with the specimen now under consideration. All 

 that can be said with regard to the latter is that while the 

 absence of a mandibular palp and the characters of the other 

 mouth-parts refer it to the genus Pasiphcea, as limited by 

 recent writers, the deep rostral tooth, the truncate telson, 

 and the relative sizes of the clielipeds seem to differentiate 

 it from all the species at present included in the genus. 



Family Acanthephyridae (?) . 



Locality. Lat. 52° 18'-1 N., long. 15° 53'-9 W. Net no. 5 e. 

 1070 fath. 21/11/98. One specimen. 



The single specimen, about 13 millim. in length, bears a 

 general resemblance to the group of larval forms for which 

 S pence Bate founded his genus Caricijphus, and in particular 

 to his C. gibberosus f, with which it agrees especially in the 

 broad laminar tooth Avith downwardly directed apex on the 

 third abdominal somite. It difl'ers in the stouter form of 

 the body and in the relatively shorter carapace, which is only 

 about one fourth of the total length. The rostrum is 

 slender, slightly longer than the eyes, having seven teeth 



* See the figure by Clau?, " Xeue Beitr. z. Morpli. der Crust.," Arb. 

 Zool. Inst. Wien, vi. 1^86, pi. iv. fig. 36. 



t ' Challenger ' Report, Macrura, p. 716, pi. cxxi. fig. 4. 



