16 SIE J. W. BAWSON ON THE MESOZOIC FLORAS OF 



the specimens iu question were found in nodular clay ironstone, associated with one of 

 the coal beds worked in the Lawsou Mine. 



A specimen of this interesting fossil, obtained, I believe, from Mr. Lawson, the mana- 

 ger of the mine, was kindly given to me last year by Mr. J. R. Byrom, one of the members 

 of the British Association ; and additional spacimens, some of them very perfect, were 

 afterwards collected by Mr. T. C. Weston of the Geological Survey. 



The modern Brasenia peltata is said to occur iu British Columbia, Japan, Australia and 

 India, as well as in Eastern America. Not being acquainted with its range of variation 

 in these countries, I cannot certainly affirm that the present specimens are specifically dis- 

 tinct. They may represent merely an ancient varietal form. 



In the same bed holding these leaves are other aquatic plants, as Pistia cornigala, 

 Lesq., Leinna sc//f(ila,^ Dn., Trapa ? There are also fragments of the greal leaves of Plataniis 

 nohilis and the Popukis and Acer described below. 



Populous LATIDENTATA, S. N. 



Base unequally pointed. Margin entire for some distance from base, then with 

 rounded obtuse teeth. Leaf broad above and probably obtuse at apex. The marginal teeth 

 are about the size of those of the modern P. grandidentata, but more obtiise, and the leaf 

 resembles in form and size the smaller and narrower leaves of the modern species, to which 

 also it conforms in the character of its venation. 



In the same matrix with the above are fragments of leaA'es of another Populus, of the 

 type of P. acerifolia, Newberry. 



Collected by T. C. "W". in Belly River series, near Medicine Hat. 



Acer Saskatchewense, S. N. 



Leaf small, unecjually tri-lobed, with the central lobe much longer than the others, 

 and the larger lateral lobe slightly notched, with a rudiment of an additional lobe. Length 

 about 4 centimetres. Width much less than length. 



This may be a terminal leaflet of a Negundo, bi\t there were no indications of lateral 

 leaves connected with the specimens, and it resembles very nearly the young leaves of 

 Acer dmycarpum. 



Collected by T. C. W. in Belly River series, near Medicine Hat. 



Trapa borealis, Heer. 



This species was recognized by me in I8Y8, iu the collections of Dr. G. M. Dawson 

 from the vicinity of the 49th parallel, in beds probably belonging to the Lower Laramie. 

 Fruits only were found. More recently Lesquereux has found in beds, probably of Lara- 

 mie age, leaves which he attributes to this genus, and which may possibly belong to the 

 present species. In Mr. Tyrrell's collections from Red Deer River, are fruits similar to 

 those previously described, and also leaves similar to those described by Lesquereux {Trapa 

 iiticro])hyUa). The leaf may be described as ovate-flabellate in form, rounded at base, 

 straight at the diverging sides, and at the end with very shallow rounded sinuses, separat- 

 ing short teeth, which in some specimens are nearly obsolete. 



' Tlie nature and affinities of this curious plant I sliall Iiojic to discuss, witli tiic, aid of tlie now speoinioiis, in a 

 future paper. 



