162 



striated, circumscribed by an acute edge. Pallial sinus tri- 

 angular, apex acute." — Zittel. 



Dimensions. — Anteroposterior and umbo-ventral diameters, 

 60 ; sectional diameter of united valves, 40 millimetres. 



Locality. — Yellow limetone of the sea cliffs at Edithburgh 

 on west side of St. Vincent Grulf ; also the Pareora and Wan- 

 ganui formations, New Zealand. 



This identification is based on the comparison with an 

 authentic specimen of the species. 



Dosinia imparistriata, spec.nov. Plate xiv., fig. 11. 

 Orbicular-cordate, rather gibbous, somewhat thin and glossy, 

 inequilateral. Umbones rather large, curved forward, and 

 situated at about one-third of the whole length from the front. 

 Lunule short and narrow, medially elevated, ornamented with 

 imbricating lainella3. 



The exterior is ornamented with linear concentric sulci at 

 variable distances from one another ; at the extremities the 

 interspaces are raised into thickish, but little elevated lamellae. 

 The posterior hiuge area is somewhat flatly rounded. 



The pallial sinus is broad, obliquely ascending to a little 

 beyond the middle of the valve, apex obtuse. 



Dimensions. — Antero-posterior diameter, 13 ; umbo-ventral 

 diameter, 12 ; sectional diameter of one valve, 4. 

 Locality. — Clayey green-sand, Adelaide bore. 

 This species is remarkable for the inequidistant concentric 

 sculpture. 



Meroe gibberula, spec. nov. Plate xv., figs. 4a— 4b. 

 Ovate-cordate, subequilateral, slightly convex, and rather 

 swollen behind the umbo ; thick, polished ; umbo acute, directed 

 forwards, a little in front of the centre ; posterior side broader 

 and truncately rounded, anterior side produced, acuminately 

 rounded. Margin of the valves closely and finely crenulated. 



Dimensions. — Antero-posterior diameter, 28 ; umbo-ventral 

 diameter, 23 ; sectional diameter of united valves, 13 millimetres. 

 Locality. — Common in the upper beds, Muddy Creek. 

 This species very closely resembles the living M. Alicice, 

 Angas, from which it differs by being more gibbous in the post- 

 dorsal region, and in consequence of which the escutcheon is 

 much broader; it is, moreover, not so truncated on the posterior 

 margin, which is not quite so long. 



FAMILY PETKICOLIM. 

 Venerupis paupertina, spec. nov. Plate xiv., fig. 15. 

 Shell ovate-oblong, moderately convex ; anterior side short, 

 somewhat acuminately rounded ; posterior side truncated, ob- 



