30 EEV. T. E. E. STEBBING — BISCATAN PLANKTON : 



intended cannot, I think, be gathered from the figures of the head in lateral view. 

 Lanceola serrata, however, is sharply distinguished from its two companions by the 

 projecting medio-dorsal teeth of the tirst four pleon-segments forming a serrate crest, to 

 which the species owes its name, and by the much more elongate telson, which is not 

 much shorter than the peduncle of the third uropods, whereas in the other two it is only a 

 little more or less than half the length of that peduncle. On the other hand, L. Loveiii 

 is with equal sharpness separated from the other two species by its first gnathopods, in 

 which the hand or sixth joint is nearly as broad as it is long, much more than half the 

 width of the preceding joint, " very thick, swollen, the anterior margin semicircular," 

 and by the fact that the third and fourth perteopods are almost equal in length. In 

 lioth limbs alike Bovallius states that the fourth joint is shorter than tlie sixth. In 

 L. (estiva, as in L. serrata, the fourth joint is longer than the sixth in the third pair, 

 Imt shorter than the sixth in the fourth pair. 



The length of each specimen, including the first antennne and uropods, was about 

 15 mm. 



Occurrences : 30 e, mesoplankton trawl. 2000 to 1000 fathoms. 1 specimen. 

 36 I. 350 to fathoms. 1 specimen. 



13. Lanceola pacifica, Stebbing. 



1888. Lanceola pacifica, Stebbing/ Challenger ' Amphipoda, Reports, vol. xxix. p. 1302, pis. 151, 152. 



This species undoubtedly comes very near to L. Sayana, Bovallius ; but whereas the 

 latter has a pronounced triangular rostrum, and is " distinguished from its allies by the 

 angular prominences of the integument of the sides " of the peraeon, the present species 

 has a small obtuse rostrum (as observed in the Pacific specimen) or is quite without one 

 (in the examples from the Bay of Biscay), and is devoid of the lateral angular prominences 

 of the perseon. Here also the back of the perseon is rounded, except for faint traces of 

 an interrupted carina on the first three segments. In L. Sayana the keel appears to 

 extend aU along the body, as Bovalhus writes, " the dorsal line forms an obtuse keel, 

 which is interrupted between the segments." He further states that " the integument 

 is thick, calcareous," epithets which will not apply to the covering of L. pacifica. 



The length of one specimen, from apex of first antenna to end of third uropod, 

 12'5 mm. ; of the other, the antennae not included, 13'25 mm. 



Occurrences: 32«'. ? 100 to fathoms *. 1 specimen (125 mm.). 

 34 b. 100 to fathoms. 1 specimen (13'25 mm.). 



Lanceola Murrayi, Norman, described and partially figured in the ' Annals and 

 Magazine of Natural History,' ser. 7, vol. v. p. 135, pi. 6. figs. 1-4 (1900), might apparently 

 be united with Lanceola felina, Bovallius, but for the difference that the first peraeojiods 

 have the hand longer, instead of shorter, than the wrist. The amount of this difference 

 cannot be estimated, as there is no detail figure of the limb for either species. 



* Cf. Dr. G. H. Fowler's "Methods and Data," supra, p. 11. 



