216 CONTRIBUTIONS TO CANADIAN PALAEONTOLOGY. 



by about eight or nine small concentric plications or imbricating lamel- 

 la, with exceedingly minute and close set radiating strise between 

 them, and its inner surface minutely papillose. Cardinal tooth of the 

 dorsal valve very small and bifid externally. Muscular and vascular 

 impressions not jDreserved. 



Dimensions of the most perfect specimens collected, (the ventral 

 valve figured) : length, seven millimetres and a Jialf ; breadth, ten mm. 



Strophalosia productoides, Murehison. 



Ortlds prodiictoidcs, ^lure.hison. 1840- Bull. Soc. Geol. de France, vol. XI, p. 254, 

 ^1. ii, fig. 7. 



Liptumi. capcraki, .1. de <J. Sl^y. 1840. Trans. Geol. Soc. Lond., L'nd Ser., vol. V, 

 p. 704, pi. liii, fig. 4, plate liv, fig. :!. 



LepUmiu cfipirata, Phillips. 1841. Pal. Foss. Cornw., I'ev- and W. Somers., p. .j8, 

 pi. XXV, fig. 98. 



Leptioia laxiqiina, Phillips. lb-, p. 59, pi. xxv, fig. 99. 



LepUrna memhranacea, Phillips. lb., p. 60, pi. xxv, fig. 101. 



Froducliis productoides, DeVerneuil. 1845. Russia and the Ural Mtns., vol. II, 

 p. 28:;, pi. xviii, fig. 4. 



Slropludosiu prroducioidi:?, Davidson. 1865. Brit. Dev. Bracliiopoda, p. 97 (which 

 see for a fuller list of synonyms that it has been thought 

 necessary to (j^uote here), pi. xix, figs. l:!-21. 



iStropIiohsia prodvctoides, Whiteaves. 1889. This volume, p. 112 (under the head- 

 ing "Productella (Strophalosia) truncata. Hall"), pi. xvi, 

 figs. 1 and 2. 



Athabasca liiver, first ten miles above the Clearwater, Dr. E. Bell, 

 1882, nine fine specimens, and opposite La Saline, about fifteen miles 

 further down the river, E. (r. McConneli, 1890, three speciiiiens. 



Productella disstmilis. 



Produclus dismrnilis, Hall. 1858. Geol. Surv. Iowa, vol. I, pt. 2, p. 497, pi. iii, 



figs. 7a-e. 

 Productus dismnilin, Meek. 1808. Trans. < Iiioago Ac. Sc, vol. I, p. 91, pi. xiii, 



fig. :!. Not Productus dissimilu, DeKoninck, 1846. 

 Productus [Productella] Hallanns, Walcott. 1884. Pal. Eureka distr. Nc\., p. 130, 

 pi. xiii, figs. 17 and 17a. 



Athabasca Eiver, — between twenty and thirty miles below the Clear 

 Water, Professor Macoun, 1875, (one specimen),— three miles below 

 the Calumet (three specimens), and thirty miles below the Red Eiver 

 (one specimen), E. '1. McConneli, 1890. 



