POLYMORPHY. 329 
instances of fasciation, 7. e. where several branches are 
fused together and flattened, we must admit that this 
flattening does not occur very often as a teratological 
appearance. 
Mr. Rennie figures and describes a root of a tree 
which had become greatly flattened in its passage 
between the stones at the bottom of a stream, and had 
become, as it were, moulded to the stones with which 
it came into contact.’ 
The spadix of Arwm, as also of the cocoa-nut palm, 
has been observed flattened out, apparently without 
increase in the number of organs. 
When the blade of the leaf is suppressed it often 
happens that the stalk of the leaf is flattened, as it 
were, by compensation, and the petiole has then much 
the appearance of a flat ribbon (phyllode). This 
happens constantly in certain species of Acacia, Oxalis, 
&e.,and has been attributed, but doubtless erroneously, 
to the fusion of the leaflets in an early state of develop- 
ment and in the position of rest.’ 
In some water plants, as Sagittaria, Alisma, Pota- 
mogeton, &c., the leaf-stalks are apt to get flattened out 
into ribbon-like bodies; and Olivier has figured and 
described a Cyclamen, called by him C. linearifoliwn, 
in which, owing to the suppression of the lamina, the 
petiole had become dilated into a ribbon-like expan- 
sion—déformation rubanée of Moquin. 
CHAPTER II. 
POLYMORPHY. 
Usvatiy the several organs of the same individual 
plant do not differ to any great extent one from another. 
One adult leaf has nearly the same appearance and 
' Loudon’s ‘Magazine Nat. Hist.,’ vol. ii, p. 463. 
* C. Morren, ‘ Bull. Acad. Belg..,’ "1852, t. xix, part ili, p. 444. 
