EEPOET ON THE GASTEROPODA. 169 



of great weight. Along with the specimen of this species which I submitted to Professor Sars I 

 forwarded another shell, sadly broken, which I consider different and new, and have named Trophon 

 auditus, from Station 150, and wbich I sent thinking it might be his Trophon clavatus. Professor 

 Sars's own letter will best convey his opinion regarding both of these forms : — " I have examined 

 your shells very closely ; they show a very perplexing similarity in form and sculpture to northern 

 Trophons. . . . The one specimen is certainly very nearly related to Trophon truncatus, Strom ; but 

 still I find, on comparing it with Norwegian specimens of the species, some differences. Thus, the 

 shell, though larger, is less solid, and the longitudinal ribs are also somewhat different both in 

 number and in form ; in all my specimens of Trophon truncatus they are distinctly lamellar and 

 reflexed ; but in your specimen they have more the appearance of simple sharp folds or keels. 

 The other specimen somewhat resembles my Trophon clavatus — thus far at least, that the ribs are 

 produced in similar tooth-like protuberances ; but the ribs are more numerous, the spire somewhat 

 more elongated, and the form of the ' cauda ' cannot be ascertained. After all, I must consider your 

 specimens distinct from Northern forms. But, on the other hand, I should not be unwilling to 

 regard both specimens as belonging to one species, and thus mere varieties analogous to the forms 

 Trophon clathratus and gunneri. Tour specimens from Kerguelen are in any case very interesting 

 as representing, even if not in my opinion an identical, yet at least a very similar and strictly 

 representative form of Trophon belonging to the Southern hemisphere." 



7. Trophon aculeatus, Watson (PL X. fig. 9). 



Trophon aculeatus, Watson, Prelim. Report, pt. 14, Journ. Linn. Soc. Lond., vol. xvi. p. 390. 



Station 122. September 10, 1873. Lat. 9° 5' S., long. 34° 50' W. Off Pernambuco. 

 350 fathoms. Eed mud. 



ShelL — Small, thin, porcellanous white, fusiform, with a high scalar spire, a blunt, 

 mamillate, one-sided apex, a short conical base, a long small snout, and angulated whorls 

 crossed by continuous thin, vaulted lamellae, projecting on the angulation of the whorls 

 into small sharp points. Sculpture: Longitudinals — there are on each whorl about 12 

 vaulted lamellse, which run continuously from below the apex to the snout ; between 

 these are a few fine lines of growth. Spirals — an angulation, strongly marked by the 

 projecting points of the longitudinal lamellse, is in the middle of the whorls. Colour 

 porcellanous white. Spire high, scalar. Apex small, blunt, mamillate, with the extreme 

 tip very much turned down on one side; the If embryonic whorls are tumid, rounded, 

 and smooth. Whorls 6 to 7, with a straight declining shoulder, angulated in the middle 

 and conically contracted below ; the conical base is produced into a narrow longish snout. 

 Suture deep and angular. Mouth club-shaped, being angulated above, and produced into 

 the long narrow canal below. Outer lip sharp, thin, and patulous on the edge ; it leaves 



1 I do not admit the distinction which Professor Sars here makes. I consider the longitudinal ribs in 

 Trophon declinans to be quite as certainly procumbent lamellse ; only this feature is somewhat obscured by their 

 being much chipped. — R. B. "W. 



(ZOOL. CHALL. EXP. PART XLIL 1885.) Tt 22 



