226 NOTES OF A NATURALIST. 



out of the stiff frozen crust under our feet a profusion 

 of delicate filmy ferns (^Hymenophylla) grew to an 

 unaccustomed size, including several quite distinct 

 species ; while here and there clumps of the stiff 

 fronds of Loinaria inagellaiiica, a couple of feet in 

 height, showed an extraordinary contrast in form and 

 habit. As Sir Joseph Hooker long ago remarked, 

 the regular rigid crown of fronds issuing from a thick 

 rhizome, when seen from a little distance, remind one 

 forcibly of a Zamia. It was to me even more sur- 

 prising to find here in great abundance a representa- 

 tive of a genus of ferns especially characteristic of the 

 tropical zone. The Gleichenia of these coasts differs 

 sufficiently to deserve a separate specific name, but 

 in general appearance is strikingly like that which 

 I afterwards saw growing in equal abundance in 

 Brazil. 



This continent, with its thousands of miles of un- 

 broken coast-line, and its mountain backbone stretching 

 from the equator to Fuegia, has offered extraordinary 

 facilities for the diffusion of varied types of vegetation. 

 As I have already remarked, some species of antarctic 

 origin travel northward, and some others, now con- 

 fined to the equatorial Andes, are most probably 

 modified descendants from the same parent stock ; 

 while a small number of tropical types, after under- 

 going more or less modification, have found their 

 way to the extreme southern extremity of the con- 

 tinent. 



By a vigorous use of my ice-axe, which is an ex- 

 cellent weapon for a botanist, I succeeded in uprooting 

 a good many plants from the icy crust in which they 



