274 87. FILICES. 



strosity, than a variety. On seeing fronds of it in the 

 herbarium of Sir W. J. Hooker, I wrote this opinion of 

 them to Mr. Newman, and was not sorry to find shortly 

 afterwards (Bot. Gaz. iv. 155) that Mr. Hort had arrived 

 at a very similar conclusion, independently, and on an 

 actual inspection of the living plant in its native station ; 

 for it seems there is now only one root left, although it is 

 stated that there were two roots originally. We might 

 soon multiply our botanical species ten-fold, if it were ad- 

 missible to make species on single plants in an abnormal 

 condition of health or luxuriance. The fact seems to me, 

 that there is a tendency in several of our species of ferns 

 to assume that widened and somewhat irregular develop- 

 ment of parts which distinguishes this A. latifolium or 

 ovatum. Cystopteris Dickieana bears the same physio- 

 logical relation to C. fragilis or dentata. My few small 

 fronds of Polypodium alpestre, gathered in Scotland, 

 particularly the one from Canlochen, exhibit that ab- 

 normal form in the widened and flattened rachis, the 

 broad and approximate pinnse and pinnules, almost 

 overlapping each other ; a peculiarity that interfered 

 to prevent me from identifying the Scottish specimens 

 with a continental example of P. alpestre in my her- 

 barium, and which is extremely like a large ordinary 

 frond of Athyrium Filix-foemina or mcisum. Perhaps, 

 the Lastrea cristata and uliginosa may be deemed in some 

 degree corresponding variations of L. spinosa, though 

 here rather regular varieties than irregular monstrosities. 

 "While something of the same kind may be seen quite 

 normal and regular in the barren fronds of Blechnum 

 boreale and AUosorus crispus. 



