.■'il2 CONTRIBUTIONS TO CANADIAN PALEONTOLOGY. 



niaxiiiium length at the base : apex placed about one-third nearer to one 

 end than to the other, nearly straight, Vjut curved very slightly towards 

 the shorter end : outline of apertui-e longitudinally subelliptical. 



Surface marked with about fifteen or sixteen regularly disposed and 

 nearly equidistant, extremely narrow and very slightly elevated small an- 

 nular concentric ridges, with flat oi' somewhat conca\'e and much broader 

 spaces Ijetween them : under a lens, too, there are indications of ijiinute 

 radiating stria'. Muscular impressions unknown. 



Height of the only specimen collected, eight millimetres ; length of the 

 same at the base, fourteen mm. ; greatest breadth at base, ten mm. 



Dawson Bay, Lake Winnipegosis, at the mouth of the Red Deei- River, 

 J. B. Tyrrell, 1889 : one nearly perfect cast of the interior of the shell, 

 with a portion of the mould of the e.xterior of the test of the same speci- 

 men. 



As the muscular impressions are unknown, it is doubtful whether this 

 shell should be referred to the Patellida'. or to the Capulidn. If it belongs 

 to the former of these two families, the apex is of course anterior to the 

 midlength, but if to the latter then the apex would be po.sterior. The 

 species is here placed provisionally in the genus I'uhfaniKKt. on account of 

 its general resemblance in external characters to such shells as the 7' 

 tijpii-<t of Hall, from the Potsdam sandstone of the State of New York, 

 and to the P. anmdata of Barrois*, and J'. Barroisii of QShlertf from the 

 Devonian rocks of France. The circumstance that the P. typica of Hall 

 was first characterized in the " Twenty-third Report on the State 

 Cabinet " in a paper bearing the general title " Descriptions of Devonian 

 Fossils,'' would seem to have misled Drs. Fischer and Zittel into the state- 

 ment that the genus Pahnaciinfa was originally based upon a Devonian 

 species. 



(S.) PliEUHOTOMAUIA OONIOSTOMA. 



P/Kurolomnrin ijoidoiloma, Whiteaves. ISUO. Trans. Royal Soc. Canada, viil. VIII, 

 Sect. 4, p. 99, pi. vi, Hg. 1. (Separate copies.) 



Dawson Bay, Lake Winnipegosis, — at Whiteaves Point, — on a small 

 island a little to the north-west of Beardy Island, — also at exposures four 

 miles west of Salt Point, — near the mouth of Steep Rock River, — and at 

 the mouth of the Red Deer River, J. B. Tyrrell, 1SS9 ; one or two .speci- 

 mens from each of these localities. 



■■' "Faune du calcaire d'Erbray.'' Mi'^in. Soc. (ie*j]. dn Xord, vol. Ill, 1889. 

 + "Sur le Devonien de.s environs d'Angers." Bull. Soc. <4«)1. de France, Ser. .% 

 XVTl, ],. 774, pi. xi.x, figs. .3 .and 3a. 



