692 REV. R. Booa watson on the 



Fleming observed, " I would venture to suggest that it is only 

 a variety of Gadus morrJiua.^^ 



It agrees witli Gadus macrocephalus, Tiles. ; but unfortunately 

 that author does not record the number of fin-rays. However, 

 the length of the Lead, size of the eye, extent of the upper jaw, 

 and the elongated ventral rayarethe same. Tilesius's example came 

 from Kamtschatka ; Kner and Steindachner's from Decastris Bay. 

 = Gadus callarias (Bloch), Griffith in Cuv. Animal Kingdom, x. 

 p. 484*, may be this species, which he observes has the upper jaw 

 longer than in Gadus morrliua ; but sucli is not shown in Bloch'a 

 figure, which appears to represent the Common Cod. 



The " Lord-fisli " of Tarrell appears to differ from this specimen 

 in the eye being smaller and the upper jaw shorter ; but it must 

 be remembered that only a coloured figure was kept. The number 

 of rays in the fins of fishes of this genus are subject to consider- 

 able variation ; but if Turton's, Tarrell's, Kner and Steindachner's, 

 and the present form are examples of the same species, the latitude 

 must be very wide indeed. 



PLATE XIV. 



Morrhua macrocephala, reduced sketch of the specimen obtained at the 

 mouth of the Thames, 1879. 



MOLLUSCA OF H.M.S. ' OHALLENGEE ' EXPEDITION. 



ly. TEOCHiDiE continued, viz. the Genera Basilissa and Trochus, 

 and the Tuebinidjd, viz. the Genus Tiirlo. By the Eev. E. 

 Booa "Watson, B.A., E.L.S., &c. 



[Published by permission of the Lords Commissioners of the Treasury.] 

 [Eead June 6, 1879.] 



The Basilissa oxytropis which follows did not present itself in 

 time to be included in the previous list. 



Of the Troclms group the Margaritas are many of theuii remark- 

 able for beauty and for form. 



The Turbos are very few ; but one is of extraordinary beauty. 



All the species now communicated are new. Some are from 

 very deep water. All throw light on a marine zone not yet 

 familiar. The list of known species presents no such features of 

 interest as to call for its publication at present. 



