SYKES : MOLLUSCA OF THE PORCUPINE EXPEBITIOX. 66 



E,ETUSA TRUNCATULA (Bnig.). 



Bulla truncatula, Bruguiere : Ency. Meth., vol. vi (1792), p. 377. 

 Return truncatula, Bruguiere : Pilsbry, Man. Conch., vol. xv, p. 205. 



"Porcupine" Expedition, 1870, Station 35; Adventure Bank, 

 92 fathoms. 



Distribution. — Coast of Norway to the Canaries ; Mediterranean and 

 Adriatic Seas (Pilsbry). Miocene and Pliocene of Europe. 



One form, from the Adventure Bank, is smaller, more uniformly 

 cylindrical, more slightly sculptured and thinner, exhibiting the 

 diaphanous bands more than usual ; this is the Bulla semisulcata of 

 Philippi (J. T. Marshall). 



Retusa (Cylichnina) tjmbilicata (Montagu). 



Bulla umhilicata, Montagu: Test. Brit., vol. i, p. 222, pi. vii, fig. 4. 

 Retiisa umhilicata, Montagu: Pilsbiy, Man. Conch., vol. xv, p. 210. 

 Cylichna umhilicata, Montagu : Locard, Exped. Scient. Trav. Talisman, 

 vol. i, p. 66. 



"Porcupine" Expedition, 1870, Stations 35 (with var. strigella, 

 Lov.), 50, 53 (with var. strigella, Lov.); Vigo Bay; Benzert Road, 

 40-65 fathoms; Adventure Bank, 92 fathoms. 



Distrihution. — Lofoten Islands and Norway, south to West Africa, 

 and in the Mediterranean, etc. (for details see Locard, I.e.). Fossil in 

 Tertiary of South Europe and Post-Tertiary of Norway. 



VOLVULA, A. Adams. 



If this name be considered to clash with Volvulus, Oken, then 

 Volvulella, Newton, may be used. Rhizorus, Montfort, has been 

 referred here, but cannot be the same, as that author states " sommet 

 enfonce, ombilique," and figures a shell well open at the apex. 



VoLVULA ACUMINATA (BrUg.). 



Bulla acuminata, Bruguiere : Ency. Meth., vol. i, p. 376. 



Volvula acuminata, Bruguiere : Pilsbry, Man. Conch., vol. xv, p. 235. 



"Porcupine" Expedition, 1870, Stations 24, 50, 56; Vigo Bay; 

 Adventure Bank, 92 fathoms. 



Distrihution. — Atlantic from Norway to the Gulf of Gascony and 

 the Mediterranean ; Gulf of Suez (Cooke). Fossil in the European 

 Tertiary. 



One box in the Museum, labelled " 2, 18, 18i," contains several live 

 as well as dead specimens. There is nothing to show in which cruise 

 they were obtained, but it may be noted that there is no Station 18J 

 in either cruise, and no Station 18 in that of 1870. 



If the suggestion made by Mr. Pilsbry as to the possible identity oE 

 this species with V. oxytata, Bush, and V. persimilis, Morch, is well 

 founded, then the range is extended to the eastern coast of North 

 America. 



The present form is not the Bulla acuminata, Sby., of the " Mineral 

 Conchology," which equals Bulla Soioerhyi, Nyst, and this, again, 

 must not be confused with the CylindrohuUa Souverhiei (Montr.). 



VOL. VI. — MARf'H, 1904. 3 



