258 MARSHAL!,: ADDITIONS TO 'BRITISH CONCHOLOGY.' 



it must not be forgotten that the fauna of the Eocene period was 

 very different from that which now exists in temperate latitudes.' 



However, Dr. Watson says that * a good deal of confusion 

 has gathered round the nomenclature of this species, and the con- 

 fusion began with Defrance,' who confounded his E. distorta 

 with another fossil shell from the Miocene and also with the 

 recent E. polita. Basterot and Grateloup followed by calling 

 the Miocene shell E. disto7-ta = E. similis d'Orb. Searles 

 Wood then identified this Miocene shell with the recent one, 

 ' but Deshayes says the fossil one is much larger and quite 

 distinct.' Philippi then applied the name of distorta to the 

 Mediterranean shell, which Desliayes subsequently corrected. 



After such a bewildering genealogy, it is well that E, 

 distorta has been assigned to the Eocene shell, and the name 

 given by Herr Weinkauff in 1867 assigned to the recent one — - 

 E. philippii. 



E. bilineata var. exigua Marsh. Dwarfed, about a line in 

 length. It is found everywhere with the type, the latter 

 being of all sizes from one line to three and three-quarters, 

 and is in this respect analogous to Cerithiopsis tuhercidaris 

 and its var. 7iana. In size and shape this variety resembles 

 E. jeffreysiana of Brusina, but the mouth of the latter is 

 smaller and the apex more pointed. 



Natica catena var. leckenbyi Marsh. (See J' Annals and 

 Mag. of Nat. Hist.' for December, 1875.) This may be 

 the var. castanea of Lamarck. It is similar to the Red Crag 

 form, and resembles N. sordida in outward appearance. 



N. affinis Gmelin. The animal of this species was described 

 by Jeffreys in the 'Annals' for April, 1877, and figured in 

 his Appendix as a British shell, I think with sufficient 

 reason. It was dredged during the ' Porcupine ' cruise off 

 the Butt of Lewis in 445 fathoms, off Shetland in 345 

 fathoms, off the S.W. of Ireland in 557 fathoms, and during 

 the ' Lightning ' cruise between the Hebrides and Faroes 



J.C, vii., Oct. 1893. 



