20 EEV. T. E. E. STEBBING— BISCATAN PLANKTON": 



length, the sixth (decidedly in the second pair and less certainly in the first) being 

 produced into a point over the base of the slender finger. 



The first and second perseopods have the fourth and fifth joints broad, with very 

 convex front margin, the fourth joint about as broad as long. Tlie fingers in all 

 the perseopods are slender, strongly curved at the tips. 



The third perseopods are without any conspicuous armature, and have no teeth or 

 serration on either margin of the second joint, the fifth joint is longer than the fourth* 

 and the sixth than the fifth. 



The fourth peraeopods are shorter than the third, the difference chiefly depending on 

 the sixth joint, which is subequal to the fifth. 



The fifth peraeopods are very slightly if at all shorter than the fourth on the whole, but 

 have a decidedly shorter fourth joint. 



The pleopods have a robust peduncle with a coupling-hook ; the rami six -jointed, with 

 a cleft spine on the first joint of the inner ramus. 



The first uropods are the longest, with the outer ramus rather less, and the inner 

 considerably more, than twice the length of the peduncle, both rami serrate on each 

 margin. The second uropods are the shortest, with the peduncle barely half the length 

 of the outer ramus, which carries some small spinules on the inner margin and is more 

 than two-thirds the length of the inner ramus. The third uropods have a peduncle 

 nearly as long as that of the first pair, but the inner ramus only as long as the outer of 

 that pair ; the outer ramus is four-fifths the length of the inner. The inner rami, as 

 already mentioned in relation to the generic characters, show some indication of being 

 jointed to the peduncle. 



Telson apparently oval, very small ; so pellucid that its boundaries could not be 

 exactly ascertained. 



Length. — From the apex of the first antennae to the end of the third pleon-segment 

 the specimen measured about one-twentieth of an inch, or 1'25 mm. With the pleon 

 unfolded this would give perhaps a total length to end of uropods of 1-75 mm. 



The species is named in compliment to M. Jules Bonnier, whose excellent account of 

 numerous sessile-eyed Crustaceans taken by the ' Caudan ' in the Bay of Biscay is well 

 known. 



Occurrence : 35 k. 400 to 300 fathoms. 1 specimen. 



Pakascina, n. g. 

 Near to Scina, but differing in the mouth-organs and uropods. First maxillae with 

 outer plate very broad, its distal border undivided and surmounted with spines and 

 spinules ; the palp one-jointed, very broad, distally vmarmed. Second maxillae with inner 

 plate rotundo- quadrate, hirsute, much broader than the somewhat conical and more 

 strongly armed outer plate. Maxillipeds having a pair of broad inner plates, the outer 

 plates almost semicircular, the apices narrowed but not lanceolate. Gnathopods and 

 pereeopods with very slender fingers. Third peraeopods with second joint not serrate. 

 The uropods all with outer branch well developed, and the inner jointed to the 

 peduncle. 



