228 



Shell (or rather cast) compressed, the maximum thickness being a 

 little more than half the height ; outline transversely subovate : anterior 

 end short and rather narrowly rounded ; posterior end longer and sub- 

 truncated below the middle ; superior border descending abruptly and 

 concavely in front of the beaks, sloping gradually and somewhat con- 

 vexly downwards behind ; umbones broad and rather prominent, beaks 

 slightly depressed, appressed and directed forwards. Surface marking, 

 hinge teeth and muscular impressions unknown. 



Dimensions : length, ninety-four millimetres ; height seventy-five 

 mm. ; maximum thickness, forty-three. 



South side of Alliford Bay : a single imperfect cast. 



The specimen is supposed to belong to the genus Cyprina on account 

 of its strong resemblance to the C. ovata of Meek and Hayden, of which 

 latter species large numbers of fine examples, with the test preserved, 

 have recently been collected by Dr. Gr. M. Dawson, E. Gr. McConnell 

 and T. C. Weston at the St. Mary's, Belly and South Saskatchewan 

 rivers. The C. occidentalis may be only a variety of C. ovata, but it 

 appears to be more transversely elongated, more truncated posteriorly 

 and more gibbous in the umbonal region. The two shells also occur at 

 very different horizons in the Cretaceous formation. 



PROTOCARDIUM HILLANUM, Sower by. (Sp.) 

 Plate 30, fig. 5. 



Cardium Hillanum, Sowerby. 1813. Mineral Conchology, Vol. 1, p. 41, pi. 14, 



fig.l. 

 " " " 1843. Pal6ontologie Frangaise Terrains Creta- 



c&, Vol. 3, p. 27, pi. 243. 



Protocardium Hillanum, Stoliczka. 1871. Palseontologia Indica, Cretaceous 



Fauna of Southern India, Vol. 3, p. 219, 

 pi. 12. figs. 8-10, and pi. 13, figs. 1-3. 



' East end of Maud Island, one perfect right valve, with the test pre- 

 served, which, however, measures only nine millimetres and a half in its 

 greatest length, and nine in its maximum height. Five small but well 

 preserved casts of a small Protocardium from the S. side of Alliford Bay 

 are also believed to belong to this species, though as the specimens from 

 both localities are all veiy small their specific identification is not alto- 

 gether free from doubt. 



