20 THE VOYAGE OF H.M.S. CHALLENGER. 



Eyes are present in Drepanophorus lanhesteri. In the (detached) posterior lobes of 

 the brain there is a double canal as in most other Hoplonemertea, the one branch taking- 

 its course along the glandular cells, the other in the ganglionic part of this brain-lobe. 



As to the sexual elements, they are in this species enclosed in sacs that are ventrally 

 situated, and although I have only one specimen at my disposal, which is just beginning 

 to ripen, I still believe I may lay it down as a rule for the species that the genital caeca 

 are arranged in pairs in the vicinity of each nerve-stem, so that four are very often 

 simultaneously met with in one section. This is, as we will presently see, a more compli- 

 cated arrangement than that which obtains in the other species of Drepanophorus, but it 

 is a simplification of the more profuse and less regular distribution of the genital sacs, as 

 it occurs in Amphiporus moseleyi. 



Amphiporus, Ehrenberg. 



Stylet in the proboscis of the normal shape. Oral and proboscidian aperture con- 

 fluent. No lateral cseca to the proboscidian sheath. Numerous longitudinal nerves in 

 the proboscis as in Drepanophorus. 



Amphiporus moseleyi, n. sp. (PI. I. figs. 20, 21; PL IX. figs. 4, 7-9, 11; PI. X. 

 fig. 3; PL XV. figs. 11, 12, 20). 



Professor MTntosh has drafted the following notes on a provisional examination of the 

 specimens before they were handed over to me, which I may here be allowed to insert : 



" A large flattened species, the largest specimens about 68 mm. in length, and about 

 12 mm. at the broadest part. The body in those best preserved is somewhat flattened 

 and with an acute edge along both sides of the tip of the tail. Anteriorly the body is 

 thick and rounded both dorsally and ventrally, but posteriorly it is much flattened. In 

 the preparation the anterior end is more pointed than the posterior. The ventral surface 

 throughout is flatter than the dorsal. 



' The larger specimens are deprived of much of their cutaneous tissue so that they 

 are comparatively pallid ; in one (the smaller) the dorsum is of a dull blackish-grey ; 

 while the ventral surface is either whitish or pale greyish. The lip of the snout is pale, 

 and from this a pale line runs backwards to the tail on each side. This is not altoo-ether 

 due to pigment, for in those devoid of cutis a very evident whitish band is found along 

 the anterior third, but it becomes indistinct posteriorly. 



' The head is somewhat truncated anteriorly and marked by a series of eyes which 

 are rather deeply seated. In the large specimens these form a marginal band on each 

 side along the antero-lateral margin of the snout. In the smaller a series begins on each 

 side of the median line of the snout and runs in a tolerably straight line backwards to 

 the slight narrowing of the furrow, whfle a somewhat triangular area superiorly is covered 



