JOURVAI. OF CONCHOLOGY, VOL. 9, K'O. 4, OCTOl'.ER, 1898. II6 



in every particular. There is only room to transcribe the first open- 

 ing sentences : — 



'■'■Chascax gen. nov. Watson. Shell spindle-shaped, strongly umbili- 

 cated, longitudinally ribbed and spirally ridged, but without varices. 

 Epidermis horny. Mouth edge angulated. Outer and inner lip quite 

 smooth. Canal long, narrow, and deep, bent a little to the left, but not 

 at all reversed in front. Operculum strong, horny; nucleus terminal, 

 internally strengthened by a broad ridge all along the right margin." 



In 1886, the "Report on the Gasteropoda collected by H.M.S. 

 'Challenger'" was published, and the Rev. R. Boog Watson names 

 as Latirus armatus Ad. the single specimen dredged on this expedi- 

 tion at Station 7 P. Lat. 28° 35' N., Long. 16° 5' W., off Teneriffe, on 

 volcanic sand, loth February, 1873.^ If we refer to his preliminary 

 paper- on the same subject, we find the shell named Fasciolaria 

 maderensis n. sp., and referred to the Turlufiella carinifera auct., non 

 Lm. Mr. Watson also expresses a doubt whether his Chascax made- 

 rensis, referred to above, may not be a very aberrant variety. These 

 remarks he repeats almost in extenso in the revised account,^ and I 

 think an examination of the Chascax in the British Museuni will 

 prove that his doubt was well founded. Indeed the Chascax made- 

 rensis is to the typical L. armatus exactly as the widely umbilicated 

 form of Latirus undatus or L. infundibulum is to the less developed 

 shells. It is the tendency of typical Latiri to form shells with this 

 (no doubt more or less monstrous) characteristic. The umbilicus is 

 deep seated, and in Miss Wilson's specimen, which is intermediate 

 between the abnormal Chascax and the moderate scarcely umbili- 

 cate L. armatus Ad.,'* the narrowness is remarkable. 



The specimen before us is of pale buff colour, decorticated, heavy, 

 seven whorled, upper whorl angulated in the middle, the upper por- 

 tion sloping to the suture, the lower straight ; the median angulation 

 is sharply noduled, the lower whorl sloping from the suture for about 

 one-fifth of its surface, then transversely angulated and conspicuously 

 sharply noduled ; below this a median portion runs nearly straight. 

 Longitudinally, once very lightly transversely lirate, followed by two 

 stronger spiral-raised somewhat noduled ribs. Towards the base are 

 two more light spiral costse, the aperture is ovate, narrowed peculiarly, 

 as if distorted by the umbilical extension, towards the canal ; the 

 outer hp is five or six times grooved ; columellar plaits almost if not 

 quite obsolete ; umbilicus narrow, but pronounced and deep ; oper- 

 culum not present. 



1 ' Challenger ' 'Gasteropoda, p. 243. 



2 /. Linn. Soc, vol. 16, p. 336, 1883. 



3 Op. cit., p. 244. 



4 Compare ' Challenger' Gasteropoda, pi. 13, fig. i. 



