lis "TERRA NOVA" EXIM-IDITIUN. 



ol'llic Imii1\' (1M. I, tin'. 5. Pr.). Tlu' nerve-layer of this pdrlimi of tlic (ir^aii (•(nitaiiis 

 si.xleeu lougitudiiial nerves. 



The armature of the prohoseis (PI. 1, tij;-. 7) is (^uite distinctive. The stylets are 

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

 liroad at the base. The functional stylet measures 0"28 mm.-0'40 mm. in length, 

 and in widtli. at the point of attachment, " 12 mm.-O • 22 mm. The hasis of the 

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

 outline. It measures 0"70 mm.-l"o mm. in length, and 0'4 mm.-0'8 mm. in 

 width at its thickest part, which is posteri(-)r. 



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

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

 contains one, or at most two, stylets. 



r,(i(li/-ir<ill. — The external epithelium stands on a comparatively thick liasement- 

 membrane (PI. I, tigs. 5 and 'J, B.M.). The circular muscle-layer is not very thick, 

 l)ut the longitudinal layer (PI. I, tigs. 5 and 9, L.M.) is well-developed, and aliout 

 equal in thickness to the external epithelium and ljasement-meml)rane together. 



('ejihalic OrgaiiK. — Each of the cresceutic apertures leads into a cavity which is 

 \vi<le ;it tirst, but soon becomes a narrower tube, circular in section, running ba(/kwards 

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

 inner end of each organ is surrcumded by the usual gaugliouic and glandular structures. 



Genital (Jrgait.^. — In Ijotli sexes the gonads are arranged in a manner xrvx similar 

 to that of A. mo.^i'lci/i ; i.e., they are distributed round the inside of the body -wall, so 

 that several ma\' be seen in the same transverse section (PI. I, tig. 9. (4.). and without 

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

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

 numerous, some of the openings are dorsal and ventral. 



Fam. PPOSTOMATID^. 



Pnif<tuiiii(. Ant. Duges, 1828. [= 7\'fr(i.^teiinnti, Ehrenberg, 1831.] 

 :i. Prosfuniii iniiiiiwiifuiii (Jouliin). (PI. I, tigs. 3, 8. Text-tigs. 1-2.) 

 'fcti-iiKtciiiiiKt iiiiiliiKiitiim [Pimuett {in Utt.)], Joubiii, I'JIU, p. 1'2 ; PI. I, tig. 9. 



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, Imt there 

 can be little doulit of the determination of these individuals. Que of them (PI. 1, fig. 3) 



* At the time of studying tlie material, only two .siiecimeiis were available. f>even more very smal 

 individuals were subsocjueiitly sorted out from among dredged material from Station 2:^0. 



