JOURNAL OF CONCHOLOGY. 319 



TROPHON TRUNCATUS (Strom.), var. SCALARIS 

 Jeffr. on the west OF SCOTLAND. 



By a. SOMERVILLE, B.Sc, F.L.S. 



(Read before the Conchological Society, February ist, 1888.) 



In October, 1887, I had the privilege of some dredging at 

 lona, and, in forty-fathom water, south of the Soay Isles, on a 

 bottom of shelly gravel, where Pedunculus valves were plentiful, 

 and Trophon truncatus (Strom.), (the type), Defrancia linearis 

 (Mont.), Nassa tncrassata (Strom.), &c. were tolerably common, 

 I obtained a dead Trophon shell of striking appearance. I 

 forwarded it to Mr. J. T, Marshall who was able to identify it 

 as var. scalaris, Jeffr. of T. truncatus (Strom.), his decision 

 being amply confirmed on a comparison of the shell with some 

 Norwegian examples belonging to the collection of the late Mr. 

 Robert Bell, London, and kindly lent to me by his brother, 

 Mr. Alfred Bell. 



This variety is described and beautifully figured in G. O. 

 Sars' work on the Mollusca of Norway, (Christiania, 1878), in 

 which it bears the name given to it by Love'n, of var. Gimneri 

 of T. clathratus, L., (a type not now inhabiting British seas, 

 though occurring in glacial and post-glacial beds), he having 

 considered it as a variety of that species. Dr. Jeffreys, in 

 referring to the variety (' British Conchology,' vol. iv. p. 320), 

 and comparing it with T. truncatus, of which he considered it a 

 form, says that its "ribs are deeper" than those of the type and 

 that *' they are also abruptly truncated and crested at the top of 

 each whorl." 



The occurrence of this shell on the West Coast of Scotland 

 is interesting, as, previously, it has not been met with further 

 south than in Shetland waters. It is to be hoped that some one 



