269 87. FILICES. 



Descends to the coast level, in the Peninsula. 



Ascends to 200 yards, or upwards, in Humber. 



Range of mean annual temperature 52 — 46. 



Native. Rupestral, Sylvestral. This is the use of a 

 name, rather than the distribution of a species. Perhaps 

 in most instances A. aculeatum intends a more highly de- 

 veloped state of A. lobatum ; but in other instances, the 

 name appears to be given to examples of true A. angulare. 

 There are specimens however so trtdy intermediate be- 

 tween the well marked forms of the two latter named 

 species, that I must confess great doubt or difficulty fre- 

 quently felt in deciding to which species they should be 

 assigned ; assuming the existence of two species, and 

 only two species, to represent the three names of angulare, 

 aculeatum, and lobatum. The plants intended by the 

 first and last of these three names, are readily distin- 

 guished by the texture and division of their fronds, while 

 we refer the intermediate or dubious forms to an inter- 

 posed A. aculeatum ; but if we quash this latter as a 

 species, the distinctions become gradually very faint in- 

 deed. On the whole, A. aculeatum, usually so labelled, 

 combines better with A. lobatum, than with A. angulare. 



1383, b. ASPIDIUM LOBATUM, Sw. 



Area 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17. 

 South limit in Devon, Isle of Wight, Kent. 

 North limit in Ross, Aberdeen, Argyle. 

 Estimate of provinces 17, Estimate of counties 75. 

 Latitude 50 — 58. British type of distribution. 

 A. A. regions. Inferagrarian — Inferarctic zones. 

 Descends to the coast level, in the Peninsula. 



