JOURNAL OF CONCHOLOGY. 225 



operculum of a Bithynia it must be wearing borrowed plumes, 

 for the operculum of H. similis is altogether diiferent ; there is 

 no similarity between the two. 



Dr. Jeffreys examined Draparnaud's original type of 

 Cydostoma simile in the Montpellier Museum, and pronounced 

 it to be our H. similis. (See 'British Conchology,' appendix, 

 vol. i, p. 310). 



By a printer's error, the locality Becton (or Beckton) was 

 printed Beeton throughout Mr. Smith's notes. 

 Sevenoaks, Torquay. 



ON THE SPECIES AND VARIETIES 



OF THE GENUS FUSUS, WHICH INHABIT THE 



SEAS SURROUNDING THE BRITISH ISLES. 



By henry K. JORDAN, F.G.S. 



(Read before the Conchological Society, April 2nd, i8go). 



Since the publication of the fourth volume of ' British Con- 

 chology,' twenty-three years ago, many interesting conchological 

 discoveries and facts have been recorded from time to time, and 

 it is probable that these records possess a greater interest in 

 relation to the genus Fusus than to any other. 



It has occurred to the writer to draw renewed attention to 

 these records, so as to make them more generally known, and 

 to add new localities and a few other notes as a small contri- 

 bution to the Conchological Society. 



In this paper, I purpose dealing only with the species and 

 varieties of Fusus which have been found alive in the seas sur- 

 rounding the British Isles ; but the question, often debated yet 

 never settled, again crops up with increased emphasis, " Within 

 what limits shall species be considered as British ?" 



Upon the answer given to this enquiry depends the inclusion 

 or exclusion of a number of interesting species. 



