i;] 



DESCRIPTION OF NEW SPECIES OF LAND AND MARINE SHELLS 

 FROM THE MONTEBELLO ISLANDS, WESTERN AUSTRALIA. 



By H. B. Tkemon, F.Z.S. 



Read 12th December, 1913. 



I'liROCGH the kindness of Mr. T. H. Ha^-nes tlie nutlioi- has heen able 

 to obtain a certain amount of material from the Montebello Islands, 

 and though the greater part consists of well-known Indian Ocean 

 forms, a few a])pear to have liitherto escaped description, and are in 

 all probability peculiar to the West Australian region, if not actually 

 to the Montebello Islands themselves. Of these species the author 

 ventures to give tlie following diagnoses. 



IIhagada montebello ensis, n.sp. 



Shell perforate, globose; whorls 4^, marked with rather coarse 



growth-lines, the last whorl somewhat rapidly descending; suture 



almost incised; umbilicus narrow, deep, partly concealed by the 



reflexed columella-margin ; columella-marjiin excavated above, 



descending in an oblicjue curve ; labrum slightly thickened, narrowly 

 retiexed, ihe margins joined by a very thin callus; aperture broadly 

 ovate. Alt. 13, diaiii. inaj. 16, miii. 13 mm. Aperture : alt. 9, 

 diam. 8 mm. 



Ilab. — Montebello Islands, Western Australia. 



Rhagada plicata, n sp. 



Shell globular, scarcely perforate, solid, wliitish; whorls 4^, the 

 earlier almost smooth, the later sculptui-ed above with fine, closely 



set, oblicjue and sliglitl}- arcuate, transverse costulse, painted with 

 a light-brownish supersutural band, which appears as a peripheral 



