the British Pandalidae. 35 



carpus is divided into five segments *. When extended 

 forwards the limb reaches a little beyond the middle of the 

 antennal scale. On tiie left side the second leg reaches to, or 

 only a little beyond, the tip of the rostrum. The remaining 

 legs just reach to, or fall a little short of, the tip of the an- 

 tennal scale. They are much more slender than in either of 

 the species above described, and the very long and slender 

 dactylus affords a conspicuous character by which the species 

 may be readily recognized (PI. IV. fig. 3, i^'). 



In the first pleopods of the male the endopod (PI. IV. 

 fig. 3, A) has almost exactly the same form as the corresponding 

 appendage of P. pr-opinquus, the outer lobe being rounded 

 and equalling, or even slightly surpassing, the internal process 

 in length. In the second pleopods of the male the appendix 

 masculina is slightly longer than the appendix interna. 



The telson has in most cases seven pairs of spines on its 

 upper surface, but in one or two cases a larger number (8-9) 

 is present, not always symmetrically placed. 



Prof. Sars' short description of the specimens referred by 

 him (with an expression of doubt) to the P. leptorhynchus of 

 Kinalian and the figures which he gives of the rostrum and 

 the second pair of legs show close agreement with the 

 specimens before me. No mention is made of the presence of 

 an exopod on the third maxillipeds ; but in reply to an inquiry 

 on this point, Prof. Sars very courteously informed me that 

 a re-examination of his specimens showed them to be possessed 

 of this appendage, so that little doubt can remain as to the 

 identity of the species. On the other hand, I do not think 

 that Sars' hesitating reference of this form to the P. lepto- 

 rhynchus of Kinahan can be sustained, Kinahan describes 

 his species as having the rostrum shorter than in P. Mon- 

 tagui, " rounded instead of compressed at the sides, wanting 

 the membranous dilatation on the under edge outside of the 

 eye." There are five spines on the carapace, separated by an 

 interval from the six spines on the rostrum, which is armed 

 below with four " very minute " teeth. The figures given 

 are somewhat crude and certainly do not suggest any close 

 resemblance to the present species. The presence of five 



* In one specimen (out of eleven examined) the carpus shows in- 

 distinct annulatioDS on the proximal side of the four normal articulations, 

 and traces of annulations are discernible even on the merua. The whole 

 limb is rather longer and more slender than usual. S. J. Smith has 

 recorded a similar variation in Jiis P. leptocerus (Proc. U.S. Nat. Mus. 

 iii. p. 4;i8, 1881). Out of several hundred specimens examined by bim 

 only six were abnormal in the segmentation of the carpus, and of these 

 one had " the right carpus multiarticulate throughout and composed of 

 about eighteen segments, nearly as in P. Montayui." 



o 



