Us "TERRA NOVA" EXPEDITION. 



of the liodv (PI. 1. fig. f), Pr.). The nerve-layer of this portion of the organ contains 

 sixteen longitudinal nerves. 



The armature of the proboscis (PI. I, fig. 7) is quite distinctive. The stylets are 

 of a blunter and stouter shape than is usual in the genus, and are particularly 

 liroad at the base. The functional stylet measures 0'2S mm.-0'40 mm. in length, 

 and in width, at the point of attachment, 12 mm.-0'22 mm. The basis of the 

 functional stylet is also very broad and stout, and is of a somewhat triangular 

 outline. It measures 0'70 mm.-l'3 mm. in length, and 0'4 min.-O ' 8 mm. in 

 width at its thickest part, which is posterior. 



The reserve stylets are contained in twenty-eight or thirty pockets, arranged in 

 a circle round the bulbous expansion of the proboscis (PI. I, fig. 7). Each pocket 

 contains one, or at most two, stylets. 



Body-wall. The external epithelium stands on a comparatively thick basement- 

 inembraue (PI. I, figs. 5 and 9, B.M.). The circular muscle-layer is not very thick, 

 but the longitudinal layer (PI. I, figs. 5 and 9, L.M.) is well-developed, and about 

 equal in thickness to the external epithelium and basement-membrane together. 



Cephalic Organs. Each of the cresceutic apertures leads into a cavity which is 

 wide at first, but soon becomes a narrower tube, circular in section, running backwards 

 and inwards to come into connection with the anterior part of the brain. The 

 inner end of each organ is surrounded by the usual gangliouie and glandular structures. 



Genital Unjana. In both sexes the gonads are arranged in a manner very similar 

 to that of J. moseleyi ; i.e., they are distributed round the inside of the body-wall, so 

 that several may be seen in the same transverse section (PI. I, fig. 9, G.), and without 

 any definite alternation with the gut-caeca. Their ducts open, for the most part, at 

 the sides of the body, but towards the hinder end, where the genital sacs are more 

 numerous, some of the openings are dorsal and ventral. 



FAM. PROSTOMATID.E. 



i, Ant. Duges, 1828. [= Tetnixteimnit, Ehreuberg, 1831.] 

 3. Proxtoniii inii/iin'tifitiii (Joubiu). (PI. I, figs. 3, 8. Text-figs. 1-2.) 

 Ti'trantciiimii unilineatum [Punnett (in lift.)], Joubin, 1910, p. 12 ; PI. I, tig. !). 



Stations 220, 339 : 45-140 fathoms. 



Of this pretty little species there are nine examples in the present collection.* The 

 type specimens in the " Southern Cross " collection are in poor condition, but there 

 can be little doubt of the determination of these individuals. One of them (PI. I, fig. ;i) 



individu 



* At the time of studying the material, only two specimens were available. Seven more very small 

 iduals were subsequently sorted out from am<m<; dredged material from Station 220. 



