104 Synopsis of Canadian Ferns and Filicoid Plants. 



The species of ferns and filicoid plants which are cer- 

 tainly Canadian, number . . .63 

 Of these there inhabit the Northern States, . 58 

 Do. do. Southern States, . 38 

 Do. do. Europe, . . 36 



The following table is designed to show some of the geo- 

 graphical relations of our Canadian ferns. The first column 

 (I.) refers exclusively to the occurrence of the species with- 

 in the Canadian boundary. The plus sign ( + ) indicates that 

 the species is general, or at least does not show any decided 

 tendency towards the extreme eastern or western, or northern 

 or southern parts of the province. The letters N, S, E, W, 

 &c., variously combined, indicate that the species is so 

 limited to the corresponding northern, southern, eastern, or 

 western parts of the province, or at least has a well-defined 

 tendency to such limitation. The mark of interrogation (?) 

 signifies doubt as to the occurrence of the species. The 

 second column (II.) shows what Canadian species occur 

 also in the Northern States, that is the region embraced by 

 A. Gray's Manual ; and the third column (III.) those that 

 extend dovm south into Chapman's territory. The fourth 

 column (IV.) shows the occurrence of our species in Europe ; 

 C in this column indicating Continental Europe, and B the 

 British Islands. The fifth or last column (Y.) shows the 

 species that extend northwards into the Arctic circle — 35 

 in all, of which, however, only 14, or perhaps 15, are known 

 to be arctic in America. Am, As, Eu, and G indicate re- 

 spectively Arctic America, Arctic Asia, Arctic Europe, and 

 Arctic Greenland. The information contained in the last 

 column has been chiefly derived from Dr Hooker's able 

 Memoir in the Linnean Transactions (vol. xxiii. p. 251). 



Hitherto no attention whatever has been paid, in Canada, 

 to the study of those remarkable variations in form to which 

 the species of ferns are so peculiarly liable. In Britain, the 

 study of varieties has now been pursued by botanists so 

 fully as to show that the phenomena which they present 

 have a most important bearing upon many physiological 

 and taxological questions of the greatest scientific interest. 

 The varieties are studied in a systematic manner, and the 

 laws of variation have been to a certain extent ascertained. 

 And as the astronomer can point out the existence of a 



