BY H. LEIGHTOX KESTEVEN. 711 



the latter that I discovered my mistake. Such an instance as 

 this calls for a most careful examination of ever}'- species dealt 

 with. 



The protoconchs treated of in this paper have occurred to me in 

 sand from various bays in and around Port Jackson, and have 

 been identified in the manner described above. 



MuREx AusTRALis, Quoy &, Gaim. 



(Plate XXXV., figs. 10-11.) 



ProtoGonch balloon-shaped, imperforate, solid, brick-red fading 

 to yellow at the tip, consisting of about one and one-half whorls, 

 defined by a rounded varix; devoid of an epidermis; sculptured 

 with slightly waved transverse ribs, as broad as their interstices, 

 and with very fine punctured revolving groove lirse, the transverse 

 sculpture becoming fainter towards the tip, leaving the first half 

 whorl ornamented only by the revolving lirse, the absolute nucleus 

 being almost smooth. Mouth almost rpund, but the short, broad 

 canal gives it a pear-shaped appearance. Outer lip thick, well 

 rounded. (The specimen figured shows the commencement of 

 the adult structure from inside the variced lip). Inner lip thin, 

 well defined. Pillar twisted. Anterior canal short, rather wide 

 and shallow: there is no sign of a posterior canal. Dimensions 

 of protoconch, length 2, breadth 15 mm. 



MuREX ANGASI, CrOSSC. 



(Plate xxxvi , figs. 6-7.) 



Ajjex thin, semi-pellucid, of about three-quarters of a whorl, 

 defined by a varix, devoid of an epidermis, its surface polished, 

 showing only very fine growth-lines. The whorl is obtusely 

 angulated high up, the varix is prominent up to this angle, where 

 it ceases, the transition from embrya to adult being marked on 

 the top of the whorl by a slight groove only, the tip of the nucleus 

 depressed. 



I have not obtained the protoconch detached. Fig. 6 represents 

 the youngest example I have. The dimensions of this specimen 

 are, length 2*3, breadth 1-.3 mm. 



