Suter. — Species of the Genus Isidora. 



273 



Fig. 4. 



Isidora novae-zelandiae, Sowerby (1873), sp. 

 Physa novce-zelandice, Sowerby, Reeve, Conch. Icon., vol. xix., 

 Physa, sp. 29 (1873). Physa novce-zealandice, Hutton, Man. 

 N.Z. Moll, p. 30. Bulinus novce-zelandice, Hedley and Suter, 

 P.L.S. N.S.W. (2), vol. vii., p. 627. Bullinus novce-zelandice, 

 Suter, Journ. de Conch., vol. xli., p. 232. 



The diagnosis of this species is also contained in Hutton's 

 Manual, and I reproduce here a figure (4) from a tracing of 

 fig. 296 in Conch. Icon. Taken from the figure the 

 dimensions are— Shell : length, 20| mm. ; breadth, 

 12^ mm. Aperture : length, 15 mm. ; breadth, 6 mm. 

 Proportions — i.= 1 : 1-7 ; ii.= 1 : 2-5 ; iii.= 1 : 1-4. 



I have only two specimens from the North 

 Island, exact locality unknown. One adult specimen 

 has smooth whorls, the other, not full-grown, is 

 shouldered. The dimensions are — Shell : length, 

 17 mm. ; breadth, 12 mm. Aperture : length, 14 mm. ; 

 breadth, Qh mm. Shell : length, 14 mm. ; breadth, 9J mm. 

 Aperture : length, 10 mm. ; breadth, 4| mm. The mean pro- 

 portions— i. = 1:1-5; ii. = 1 : 2-2 ; iii. = 1 : 1-3. The adult 

 specimen is of chestnut-colour, the young horny-olive. The 

 spire is shorter and the last whorl not quite so broad posteriorly, 

 nor so flat at the periphery, as the figure of the type indicates. 

 Type in Mr. Sowerby 's cabinet (?). 



Isidora antipodea, Sowerby (1873), sp. 

 Physa antipodea, Sowerby, Reeve, Conch. Icon., vol. xix., Physa, 

 sp. 37 (1873). Physa antipodea, Hutton, Man. N.Z. Moll., 

 p. 30. Aplexa antipoda, Hutton, P.L.S. N.S.W., vol. vii., 

 p. 67. Bulinus antipodeus, Hutton, Trans. N.Z. Inst., vol. xvii., 

 p. 56. Bulinus antipodeus, Hedley and Suter, P.L.S. N.S.W. 

 (2), vol. vii., p. 627. Bullinus antipodeus, Suter, Journ. de 

 Conch., vol. xli., p. 233. 



Diagnosis in Hutton's Manual. I reproduce here (fig. 5) the 

 outlines of the species after Reeve. This seems, as 

 far as our scanty knowledge goes, to be the only one 

 of our species that has constantly smooth whorls. 

 The dimensions taken from the figure are — Shell : 

 length, 22 mm. ; breadth, 12 mm. Aperture : length, 

 13 mm. ; breadth, 6| mm. Rationis — i. = 1:1-8; 

 ii. = 1 : 2 ; iii. = 1 : 17. 



This species is represented in my collection by two 

 specimens from Lake Wakatipu, and the dimensions 



are — Shell : length, 17 mm 

 Aperture : length, 11 mm. ; breadth, 5i 



18|mm. ; breadth, 11 mm. 

 18— Trans. 



breadth, 10| mm. 



mm. Shell : length, 



Aperture : length, 12 mm. ; breadth, 



