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



This is a species beautiful in form and in texture. With, some superficial resemblance, it differs 

 from Trophon acanthodes, Wats., in its continuous longitudinal lamellae, the thinness of its shell, the 

 delicacy of its surface-texture, and the form of the base. In the latter respects it recalls Trophon 

 vaginattis, Jan ; but, than that species, it is less carinated, has a more contracted shorter base, a 

 finer snout, and the spines are much more distinctly connected with the continuous lamellae. 

 Trophon coronatns, H. and A. Ad., a New Zealand form, and which extremely resembles Trophon 

 goodridgii, For., has a much longer canal, a more tumid body, more numerous varices, with shorter 

 spines, not rising, as here, in a coronal round the spire. Trophon laciniatus, Martyn, from Van- 

 couver's Island, presents a variety slightly resembling the Challenger species ; but the snout is 

 much shorter, the base more produced ; the spines, too, are very much shorter, and, rising near the 

 suture, project upwards parallel to the spire. 



6. Trophon declinans, Watson (PI. X. fig. 10). 



Trophon declinans, Watson, Prelim. Report, pt. 14, Joum. Linn. Soc. Lond., vol. xvi. p. 388. 



Station 144a. December 26, 1873. Lat. 46° 48' S., long. 37° 49' 30" E. Off 

 Marion Island. 69 fathoms. Volcanic sand. 



Station 150. February 2, 1873. Lat. 52° 4' S., long. 71° 22' E. Between 

 Kerguelen and Heard Islands. 150 fathoms. Coarse gravel. Bottom temperature 3 5 "2°. 



Shell. — Thin, chalky white with a tinge of buff, fusiform, with a high subscalar spire, 

 small mamillary apex, long small snout, rounded whorls scored by thin procumbent 

 lamellae. Sculpture: Longitudinals — there are on the later whorls from 15 to 20 pro- 

 cumbent lamellae, between these are slight lines of growth. Spirals — there are a few 

 quite irregular and obsolete rounded threads. Colour chalky white with a tinge of buff 

 Spire high, subscalar. Apex small, consisting of barely two smooth, globose, embryonic 

 whorls, of which the extreme tip is slightly turned down on one side and immersed. 

 Whorls 7, slightly flattened above, convexly cylindrical below, with a very slight con- 

 traction above the suture ; the last is a little tumid, with a produced conical base running 

 out into a long, small, twisted, and upturned snout. Suture slightly imj>ressed, oblique. 

 Mouth oval, bluntly pointed above, drawn out into the long, narrow, and oblique canal 

 in front. Outer lip thin, arched, slightly reverted and patulous ; very obliquely cut off 

 and emarginated at the point of the canal. Inner lip very concave above, convex at 

 the entrance to the canal, from which it runs with a twist and very obliquely to the left ; 

 the labial glaze is thin and somewhat indefinite. H. 0'8 in. B. 0"32. Penultimate whorl, 

 height, 0-17. Mouth, height 0*43, breadth 0'2. 



I have described this as a new species with very great reluctance. My own opinion is that it is 

 a large thin variety of Trophon truncatus, Strom ; and that opinion is shared by Mr E. A. Smith. 

 Dr Gwyn Jeffreys, however, and Professor G. O. Sars decidedly hold it as distinct ; and their 

 extensive accpiaintance with the large northern variety of Trophon truncatus makes their judgment 



