86 Gatliff and Gabriel : Marine Mollnsca. 



form bundles of three or more. The shell is invested with a 

 very thin olivaceous epidermis. Interior somewhat iridescent. 

 Muscular impressions strong, the anterior oblong and the pos- 

 terior subcircular. Pallial line not sinuated. Hinge simple, 

 the characteristic curved tooth of the juvenile form having be- 

 come almost ol)Solete. The post-dorsal edge of valves is dehis- 

 cent. 



Dimensions of Type. — Length, 7.5 ; breadth, 3.75 ; depth of 

 single valve, 1.5 mm. 



Locality. — Dredged off Point Cook, Port Phillip, 8 fathoms 

 (type locality). Type taken alive. Dredged off Portsea, Port 

 Phillip, Frankston and Dromana (T. Worcester). 



Obs. — In the young condition, the hinge exhibits a rather 

 prominent, much curved tooth in the right valve, with a cor- 

 responding cavity in the left, thus presenting a character differ- 

 ing in its entirety from the senile form. This is characteristic of 

 the genus Sorirava, and it was the young form of ^S'. rugosa, 

 Linn., Avhere Daudin erred in erecting his genus Hiatella. 

 Superficially the species much resembles a North American 

 palaeozoic shell, Modiomorpha suhalatd, Conrad, but the hinge 

 alone severs it from that genus. Like other representatives of 

 Saricava, the present one is variable, several specimens show- 

 ing moi'e pronounced alation. The angular form and granular 

 surface serve as useful recognition marks, but -with beach-worn 

 specimens, the latter is difficult to discern. The irregular 

 dehiscence of the valve-edges is not seen on all the specimens, 

 and is not confined to the post-dorsal edge. 



Type in Mr. C. J. Gabriel's collection. 



EXPLANATION OF PLATES XVIIL, XIX. 



Columbella remoensis, sp. nov. 

 Columbella franklinensis, sp. nov. 

 Leiostraca josh nana, sp. nov. 

 Cyclostrenia microscopica, sp. nov. 

 Cingulina magna, sp. nov. 

 Cingulina rhyllensis, sp. nov. 

 Saxicava subalata, sp. nov. 

 All figures variously magnified. 



