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attain, though this is more particularly the case with the Cephalopoda. 

 Thus, one of the Receptaculitidee ( Receptaculites Oweni), which is abun- 

 dant in these limestones, is known to attain to a size of twelve or even 

 twenty inches in diameter. Some specimens of a simple Cyathophylloid 

 coral ( Streptelasma rohustum) from Lower Fort Garry are nearly seven 

 inches in length, as measured along the convex curve, and nearly five 

 inches in height. A brachiopod from the same locality (Rafinesquina 

 lata) is rather more than three inches in length at the hinge line, and a 

 specimen of Strophomena incurvata from East Selkirk is fully double the 

 usual size of that species. One of the gasteropods (Maclurea Manito- 

 bensis) of these limestones is sometimes as much as eight inches and a 

 half in diameter, and another (the Sormotoma Winnipegensis of this 

 Report) is eight inches long. The "gigantic Orthoceratites" noticed by 

 Sir John Richardson on the west side of Lake Winnipeg, have already 

 been referred to, but these are from localities north of the Saskatchewan. 

 South of that river, at Dog Head, specimens of Orthoceratites (probably 

 of Endoceras suhannulatum), four feet and a half or even six feet in 

 length, and imperfect at both ends, were observed by Mr. Lambe in 

 1890. A siphuncle of Endoceras crassisiphonatum, which is also imper- 

 fect at both ends, is nearly three feet long. A specimen, which appears 

 to be a cast of the anterior end of the body chamber of a specimen of a 

 Poteriooeras (probably P. nohile), recently collected by D. B. Dowling 

 and L. M. Lambe at Berens Island, and showing the infolding of the 

 lip, is seven inches across. Rough casts of the interior of spirally coiled 

 discoidal or nearly discoidal shells, apparently allied to Barrandeoceras, 

 from several localities on the west shore of Lake Winnipeg, are nearly or 

 quite two feet across. Lastly, a free cheek of a trilobite, Asaphus (Iso- 

 telus) gigas, from Cat Head, indicates a specimen that must have been 

 twenty inches in length when alive ; and other similar examples could be 

 given. 



The writer is much indebted to Mr. E. O. Ulrich, of the Geological 

 Survey of Minnesota, for valuable information in regard to the polyzoa, 

 pelecypoda and some of the gasteropoda that are enumerated or described 

 in this report ; to Mr. Charles Schuchert, of the United States National 

 Museum, for assistance in the determination of some critical species or 

 peculiarly preserved specimens of Strophomenidse; to Professor T. Rupert 

 Jones for the description and drawings of Aparchites parvulus ; and to 

 the proprietors of " Palseontographica" for permission to reproduce the 

 figures of Aulocopina Winnipegensis in that publication. 



