428 GASTROPODA. [Pectmibranckia. 



Type in my collection. 



Hob. Te Onepoto, near Lyttelton, type (H. S.) ; Kawau Island 

 (C. Spencer). 



Genus 2. DRUPA, Bolten, 1798. 



Drupa, Bolten, Mus. Bolten. (2), 1798, 55. Type : Ricinul'i horrida, Lam. 

 Canrena, Link, 1807. Sistrum, Montfort, 1810. Ricimtle, Lamarck, 

 1812. Ricinula, Lam., 1816. Ricinella, Schumacher, 1817. Morula, 

 Schumacher, 1817. 



Animal and radula the same as in Thais. 



Shell ovate or subfusiform. solid ; whorls tubercular, spinose, or 

 longitudinally costate ; aperture narrow, oblong, canaliculate above, 

 with a short canal below ; outer lip furnished with strong teeth within ; 

 inner lip wrinkled or plicated. Operculum oval, straight, with lateral 

 nucleus. 



The genus is essentially Polynesian in distribution, but occurs also 

 in Australia, Tasmania, &c. 



Fossil in the Tertiary ; not in New Zealand, but an Eocene species 

 is known from Tasmania. 



1. Drupa Bollonsi, Suter. 1906. Plate 19, fig. 11. 



Purpura striata, subsp. Bollonsi, Sut., T.N.Z.l...xxxviii, 1905 (1906), 331. 

 Drupa Bollonsi, Sut., P. Mai. S., viii, 254, pi. 11, f. 5-7. 



Shell rather small, ovate, solid, white, with nodulous cinguh. 

 Sculpture consisting of strong, somewhat unequal, flatly convex spiral 

 ribs, 3 on the penultimate and 7 on the body whorl, generally com- 

 posed of 4 to 6 fine spiral threads, the interstices usually a little 

 narrower than the ribs, containing sometimes a fine spiral thread ; the 

 cinguh are cut up iato distinct nodules by more or less deep axial sulci ; 

 growth-lines close, oblique, lamellar, reticulating the fine spiral sculp- 

 ture ; fasciole distinct, lamellar, leaving a deep groove between it 

 and the inner lip. Colour yellowish- white, aperture white within, the 

 outer lip sometimes yellowish or light purple. Spire conic, very 

 variable in height, mostly a little less than the height of the aper- 

 ture. Protoconch minute. Whorls about 6, flatly convex on the spire, 

 the body-whorl usually more convex, contracted above the fasciole. 

 Suture well impressed. Aperture subvertical, ovate, channelled above, 

 produced below into a short open and deeply notched canal. Outer 

 lip convex, crenulate, much thickened inside, very strongly dentate- 

 lirate. Columella subvertical, almost straight, twisted and tapering 

 below. Inner lip moderately broad, very broadly extended over the 

 somewhat concave parietal wall, which bears a small tubercle below 

 the suture, with 3 transverse median folds ; excavated below, with a 

 free edge bending over the groove margining the fasciole. Oper- 

 culum with the nucleus lateral. 



Diameter, 19 mm. : height. 32 mm. (largest specimen. 6 whorls). 

 Diameter, 16mm. ; height. 22 mm. (small specimen, 6 whorls). 



