SOS CONTKIBUTIONS TO CANADIAN PALEONTOLOGY. 



.Surface max'ked with numerous fine and closely disposed rounded or 

 flattened radiating rilxs, which are crossed bj' concentric stria' of growth. 

 Muscular impressions and hinge dentition unknown. 



Dawson Bay, Lake Winnipegosis, about two miles west of Salt Point, 

 and at the mouth of the Red Deer River, J. B. Tyrrell, 1889 : one imper- 

 fect left valve fiom each of these localities. 



The radiating costa' of the larger of these two valves (fig. 1) are about 

 one millimeti-e broad in theii- thickest part, and those of the smaller (fig. 2) 

 less than half a millimetre in breadth. In the absence of any knowledge 

 of the hinge dentition of the valves this species is here provisionally 

 referred to Ciirdiopgis, on account of its resemblance in external charac- 

 ters to the C. rndiafa of Meek and Worthen, as figured by Hall,* but it 

 may be a I'ararni. It differs, however, from C. niiUala in its more nearly 

 circular outline, and in the position of its beaks, which are not placed 

 neai'ly so fai' foi'ward. 



Three casts of the interior of a shell, collected by Mr. Tyrrell, in 1889, 

 at Whiteaves Point, in Dawson Bay, are also probably referable to C. 

 tenuico!<tat<i,, though they show no traces of the radiating ilbs character- 

 istic of the exterior of its test. 



(S-) Cypricardella bellistriata, Conrad. (Sp.) 



Plate 40, figs. 4 and .5. 



Jflrro/loii. lu-IIUtrinIa, Conrad. 184-2. Journ. Ac. Nat. Sc. Phil., vol. VII, p. 247, pi. 



xiii, fig. 12. 

 Hall. 1843. Oeol. Surv. N. York, Rep. Fourth Distr.,p. 196, 



fig. -2. 

 Hall. 1873. Twenty-third Reg. Rep. N. Y. St. Cab. Nat. 



Hist., pi. xiv, tig. 8. 

 Eodov Im-IIUi rial IIS S. A. Miller. 1877. Cat. Am. Pal. Foss., p. 244. 

 j)firroiloiii'lla I III 1 1 Itl rial a, (Ehlert. 1881. Mem. Geol. Soc. France, 3rd Ser. , vol. II, 



p. 27, pi. iv, figs. 4a, 4b. 

 Mirrodoii (Giiprimnklla) hi;IJi«triatii,% Hall. 188,5. Pal. St. N. York, vol. V, pt. 2, 



Lamellibr., 2, p. 308, pi. xln, figs. 17-20; pi. Ixxiii, figs. 



7-22; and pi. Ixxiv, figs. 5-10. 

 Cfr. Saiii/niiio/aria lamii/losa, Coldfuss. 1834-40. Petrel Germ., vol. II, p. 270, pi. 



cUx, fig. 12. 



Dawson Bay, Lake Winnipegosis, about two miles west of Salt Point, 

 J. B. Tyrrell, 1889 : one mould of the exterior of both valves. Two casts 

 of the interior of a shell which is probably referable to this species, both 

 of which are figured on plate xl, were collected Vjy Mr. Tyrrell, in 1889, 

 in the Upper- Devonian shales at Point Wilkins, in Dawson Bay. 



" On PI. Ixx, fig. 2.0, of vol. V, |it. 1, Lamellibr., 2, of the Pal. St. N. York. 



