58 CONTRIBUTIONS TO CANADIAN PAL.'-EONTOLGGT. 



Anodonta propatoris ? White. 

 Plate 9, figs. 2 and 2 a. 



Anodonio, propatoris, White. 1877. Bull. U. S. Geol. Surv. Terr., vol. III., p. 601. 

 " " White. 1880. U. S. Geol. Surv., Contr. to Pal., Nos. 2-8, p. 61^ 



pi. 24, figs. 2a, b, c and d. 



White. 1883. Rev. Non-:Marine Foss. iloU. N. Am., p. 23, 

 pi. 19, figs. (>, 7, 8 and 9. 



Forty-ninth Pai-allel, six miles west of the first or South Branch of 

 the MilkEiver, G. M. Dawson, 1874, H. M. Xorth American Boundaiy 

 Commission : one good specimen. Big Island bend, on the Bell)^ River, 

 G. il. Dawson, 1881 : a few badly preserved casts of the interior of the 

 shell. Milk Eiver Eidge, E. G. McConnell, 1S82 : six casts of the 

 interior of the united valves, with large portions of the thin test 

 preserved. South Saskatchewan, eight miles above the mouth of the 

 Eed Deer Eiver, E. G. McConnell, 1883 : abundant. Red Deer River, 

 Township 21, Eauge 12, west of 4th Principal Meridian, R. G. McCon- 

 nell, 1883: two small casts. Near Bull's Head, E. G. McConnell, 

 1883 : three casts of the interior of the adult shell. 



The characters of the interior of the valves are not at all clearly 

 shewn in any of the specimens from these localities. The hinge line 

 appears to have been thin and edentulous, but it is impossible to ascer- 

 tain definitely whether the pallial line had a sinus or not. 



The form and surface markings of the exterior of the shell, which is 

 nearly all that the Canadian specimeus shew, are as much like those of 

 the so-called Thracia ! Kubtortuo&a of Meek* as those of Anodonta projia- 

 toris, and it is not at all unlikely that some if not all of the fossils now 

 under consideration should bo referred to the former species rather 

 than to the latter. 



All the specimens cidlected by Dr. Dawson and yh\ McConnell prior 

 to 1883 were at first and for a long time supposed by the writer to be 

 conspecific with T. suhtortuosa. This opinion, too, seemed to be con- 

 firmed by the circumstance first that their tests showed scarcely any 

 traces of an inner nacreous layer, and secondly by the fact that at 

 Milk River Eidge they were obtained from a series of beds which hold 

 2Iactra alta (which occurs with T. suhtortuosa at the mouth of the 

 Judith Eiver in Montana), and such other marine types as Pterin 



* Rep. U. S. (jeol. Surv. Ten-., vol. IX., r. '-123, i.l. 36, fig. 5. 



