WHITEAVES.] DEVONIAN FOSSILS OF MANITOBA, ETC. 305 



a wax impression of one of these moulds, in which the valves are thirty 

 millimetres in length and nearly thirty-two in height. 



The writer has failed to find a single character by which these speci- 

 mens from Lake Winnipegosis can be satisfactorily distinguished from 

 the Lucina antiqiuc, of the Devonian rocks of the Eifel, as described and 

 figured by Goldfuss. The phrase " umbonibus postmedianis ' of the ori- 

 ginal description of that species, it is true, is not applicable to any of the 

 specimens collected by Messrs. Tyrrell and Dowling, but in Goldfuss's 

 figures of L. antiqua, the umbones and beaks are represented as placed a 

 little in advance of the midlength. 



Judging by the descriptions and figures of both, it is difficult to see 

 upon what grounds the Pdracyclas Ohioennix of Meek is separated from P. 

 o/ntiqua. Each of the eight specimens from Lake Winnipegosis is cha- 

 racterized by the " strongly oblique sulcus, extending from the back part 

 of the beaks to the upper part of the posterior margin,'' on the "posterior 

 dorsal slope of each valve," which Mr. Meek relies upon as the distin- 

 guishing feature of /■' Ohiaensis, but which is equally characteristic of P 

 aittiqii.a. 



Paracyclas elliptica, Hall. 



Paracyrlai cHiptica, Hall. 1843. Geol. Surv. N, York, Rep. Fourtli Distr., p. 171, 



pi. Ixvii, fig. 2. 

 Lucina ( Paracyclas) ellipHca, var. occidetitalU^ Hall and Whitfield. 1882. Twenty- 

 fourth Reg. Rep. N. York St. Mus. Nat. Hist., p. 189. 

 Paracyclas elliptica, Hall. 1883. Pal. St. N. Y'ork, vol. V, pt. 1, Plates and Expla- 

 nations, pi. Ixxii, figs. 23-30. 



1885. Pal. St. N.York, vol. V, pt. 1, Lamellibr., 2, p. 440, pi. 

 Ixxii, figs. 23-.33, and pi. xcv, fig. 18. 



A few specimens of the large and typical form of this species were col- 

 lected by Messrs. Tyrrell, Dowling and the present writer, in 1888 and 

 1889, at Onion Point, Lake Manitoba, and at many of the exposures on 

 the shores and islands of Lake Winnipegosis. 



Paracyclas elliptica, var. occidentalis, Billings. 



Plate 39, figs. 7-10. 



Lucina occidentalis, Billings. 18.59. In Hind's Rep. Assinib. and Saskatch. Expl. 



Exped., p. 187, wood-cut, figs, lb, c. 

 Lucina elliptii-a, Billings, as of Conrad. 1859. lb., p. 187, wood-cut, fig. Id. 

 Paracyclas Billingsana, S. A. Miller. 1883. Am. Pal. Foss., Second Ed., p. 311. 



In 18.58, Professor H. Youle Hind collected two lamelli branchiate 

 shells, which are still in the Museum of the Survey, from the Devonian 



