68 llev. Canon Norman's Revision 



Distribution. ]iay of Jiiscay, ' Travaillcur ' [Je.ffreyH)) ; off 

 Azores, 450-1000 fathoms, ' Clialleng-er ' ( Watson) ; Azores, 

 1287 metres {Dautzenherg) ; ' Blake,' Stat. 43, lat. 24° 8' 

 N., long. 82° 51' W., 339 fathoms {Dall). 



Fossil. Middle Pliocene of Calabria {Seguenza). 



Mr. E. A. Smith has kindly, at my request, compared the 

 s])ecimens of this species which are in the British Museum 

 with the figures and description of D. Guernei, Dautzenberg. 

 and has confirmed my expectation that the latter cannot be 

 regarded as specitically distinct from B. seinilevis. It is clear 

 also, I think, that B. ehurnea, Dall, is the same thiug. 



Genus 2, Haminea, Leach. 



47. IJaminea hydatis (Linn.). 



Yar. glohosa, Jeffreys. 



Genus 3. Aceka, Miiller. 



48. Acera hullata, Miiller. 



Var. 1. nana^ Jeffreys. Length -jV inch. 

 Var. 2. Farrani, Norman. Length If inch. 



Ahera bullrda, var. yicjantea^ Norman, Museum Normau- 

 iauum, iv. Mollusca, 1888, uo. 101. 



The variation in size in this species is most extraordinary, 

 and ])erha[)S the forms here treated as varieties should rather 

 be regarded as entitled to rank as s})ecies. The full size of 

 ordinary specimens may be taken as an inch ; but no Sj)cci- 

 mens of var. nana, which was dredged by Jeff'reys and 

 myself in shallow water at Balta Sound, Shetland, exceed 

 three twentieths of an inch. On the other hand Dr. Farran 

 i'ound many years ago (see Nat. Ilist. Keview, vol. iv. (1857) 

 p. 74) the gigantic variety which I here name after him. 

 The specimens were dredged near Birterbuy Bay, L'eland : 

 the animal measured 3 inches long and 2^ wide, and 

 weighed 2^ ounces. The shell of one of these giants, now 

 in my collection, measures 1| inch long and an inch wide ; 

 hundreds of specimens of var. nana might be placed in 

 it as in a box! In 1870, in company witli my friend Mr. 

 David Koberlson, 1 dredged diligentl>' the S[)ot carefully 

 described by Farran, but without again meeting with this 

 form ; but Mr. A. G. More informed me that the year before 

 that just mentioned he had found a similar-sized specimen in 

 a lough nearer Galway. 



