182 



convex, medially depressed. Anterior and posterior extremities 

 about equally rounded ; ventral and dorsal margins nearly 

 parallel ; front dorsal margin a little incurved ; post-dorsal 

 margin nearly straight, gently sloping, perceptibly attenuated 

 towards the extremity. IJmbo small, acute, recurved. 



Pallial sinus broad, truncately rounded at the end, almost 

 reaching to the anterior adductor scar. 



Surface shining ; sculpture consisting of concentric growth- 

 lines and fine striae, radial stria? on the anterior and posterior 

 slopes, and of oblique distant engraved lines posterior to a line 

 joining the umbo and the antero -ventral margin. The oblique 

 lines of sculpture are nearly straight on the medial portion of 

 the valve, crossing on to the post-dorsal slope in a gentle curve. 



Dimensions — Antero-posterior diameter, 295 ; umbo-ventral 

 diameter, 12 '5 millimetres. 



Locality. — Lower beds at Muddy Creek {J. Dennant .') 



Solecurtus Dennant i differs from the foregoing species in 

 beiug more rounded anteriorly, more attenuated posteriorly r 

 less inequilateral, narrower, and in the fewer and simpler 

 oblique lines of sculpture. 



Solecurtus ellipticus, spec.nov. Plate xvi., fig. 14. 



Transversely ovate-oblong, thin, translucent, inequilateral y 

 posterior side about five-eights of the whole length; somewhat 

 attenuated at both ends, obliquely rounded in front, broadly 

 rounded behind ; the dorsal margins straight, the front part 

 sloping more rapidly than the other. 



The oblique lines of sculpture are distant, a little curved on 

 the medial portion of the valve, roundly turned back as they 

 cross on the dorsal slope. 



Dimensions. — Antero-posterior diameter, 16; umbo-ventral 

 diameter, S millimetres. 



Locality. — Gastropod-bed in the Eiver Murray Cliffs, near 

 Morgan. 



This species differs from the two former by its sloping dorsal 

 margins ; in the arrangement of its sculpture-lines it approxi- 

 mates to S. Dennanti, of which it may possibly be a young ex- 

 ample. Compared with S. candidus, it is distinguished by its- 

 sloping dorsal margins, and therefore more attenuated ex- 

 tremities ; the umbonal ridge is obsolete, and consequently the 

 sculpture-lines are curvilinear and not angulated, they are r 

 moreover, wider apart. 



FAMILY PHOLADID.E. 

 Barnea tiara, spec. nov. Plate xviii., figs, la— lc. 

 Narrowly-elongate, inequilateral, the umbo situated at three- 

 sevenths of the whole length from the front, attenuated at both 



