Tertiary.'] PALEONTOLOGY OF VICTORIA. IMollusca. 



Very abundant in the ferruginous Lower Pliocene Tertiary 

 strata of Flemington, north of Melbourne. One unusually large 

 specimen presented by Mr. Brough Smyth is 3J inches in length. 



Explanation of Figures. 



Plate XXVI. — Fig, 1, Large specimen, witli ordinary cliaracter of radiation, natural size. 

 Fig. 2, smaller specimen, witli a few of tlie undulations presenting an unusual appearance of a 

 ridge-lilie continuity. Fig. 2a, portion of surface magnified to slxow the striation. 



Plate XXVI., Figs. 3-9. 

 CERITHIUM FLEMINGTONENSIS (McCoy). 



[Genus CERITHIUM (Buuo). (Sub.-kingd. Mollusca. Class Gasteropoda. Ord. Pectini- 

 braiichiata. Fam. Ceritliiidje.) 



Gen. Char. — Shell of very numerous gradually-enlarging whorls ; spire longer than the 

 body whorl ; the outer lip usually dilated ; aperture oWique ovate, terminating in front in a short 

 canal slightly recurved and bent to the left ; inner lip usually with a faint spiral ridge above 

 and below defining two internal canals ; external surface usually sulcated spirally.and with more 

 or less distinct varices.] 



Description. — Spire acute, apical ang-le about 25° of upwards of 10 flattened 

 wLorls; body wborl with the outer lip slig'htly ascending' and dilated ; surface with 

 fine nearly equal spiral striae (alout 30 between the sutures), crossed b}' close obtuse 

 and slig'htly sig-moid rounded ribs (about 20 in a whorl), most prominent at the 

 lower or anterior end next the suture, becomintj' generally indistinct at less than 

 half-way to the suture above, but a few here and there extending' singly across the 

 whole space from one suture to the next, like a varix. Spiral striae on base or 

 anterior half of body whorl coarser than on spire, and every third or fourth larger 

 than the rest. Internal casts rounded, smooth on turns of spire, frequently showing 

 a few longitudinal obtuse ribs on body whorl, the dilated outer lip of which is some- 

 times faintly marked with spiral ridges. Length from 2 to 5 inches ; proportional 

 width of body whorl, -y^j/^ ; length of body whorl, including canal, -^^^^ ; length of 

 penultimate whorl, ■^'^\. 



The genus Cerithium abounds in shallow waters near the 

 mouths of great rivers in tropical countries at the present day, 

 and in the Older Tertiary deposits it has its maximum of local 

 develojjment. 



The present species obviously varies a little in apical angle and 

 consequent relation of length to width, although I have never yet 

 seen a sufficiently perfect specimen to enable me to be certain of 

 the number of the whorls ; and this is a point which any amateur 



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