716 STtfDlES ON AUSTRALIAN MOLLOSCA, xili., 



596, for B. acuminata, etc. Volvulella Newton, Syst. List. Brit. 

 Oligocene, Eocene Moll., 1891, pp. xii., 268, for Volvula Adams, 

 not Oken, 1815. 



Some discussion has occurred over the validity of tlie name 

 Volvula. On the ground that Volvuhis Oken, 1815, preoccupied 

 Volvula Adams, 1850, Mr. R. Bullen Newton replaced it, in 1891, 

 with a new name, Volvulella. But, as Dr. H. A. Pilsbry con- 

 sidered that it was not thus invalidated, he employed Volvula 

 in his monograph of the genus in the Manual of Conchology, in 

 1893. 



Neither of these authorities seems to have seriously considered 

 the claim of Rhizorus. As early as 1810. Rhizorus adelaidis 

 was legitimately proposed by Montfort, for a shell the size of a 

 grain of millet, found on a sandy beach at Porto Feirajo, in the 

 island of Elba, Italy. From a rough, reversed, but recognisable 

 woodcut, it seems clear that Ji. adelaidis is Bulla acumlvntn. 

 liruguiere, 1792,* because that is the only Mediterranean shell 

 which corresponds in size and contour. This is itself the type, 

 both of Volvula and of Volvulella so, as was indicated sixty 

 years ago by Menke,t Rhizorus must be given precedence. 'I he 

 Australian species concerned in this change of nomenclature are 

 Volvula rostrata A. Adams, V. sulcata Watson, and V. traqula 

 Hedley. 



Odostomia pascoei Angas. 

 (Plate xlvi., fig.5.) 



Odostomia pascoei Angas, Proc Zool. Soc, 1867, p. 112, PI. 

 xii., 6g.l2. 



In the Natural Histor}' Museum at South Kensington, I ex- 

 amined a single specimen, marked as the type of 0. pascoei, and 

 seven specimens marked as types of 0. kreffti Angas. These 

 two agree in all particulars, except that 0. pnscoei has an addi 

 tional whorl, and a corresponding increase in length and breadth. 

 Since it is the adult which 0. pasc<iei represents, and since that 



*. Jeffreys, Brit. Conch., iv., 1867, p.412. 

 tMenke, Malak. Blatt., i., 1854, p. 46. 



