OHA Pare ne PP. 
ENATION. 
Unper the above heading are included certain forms 
arising from excess not of growth, but of development, 
and consisting in the formation of supplementary lobes 
or excrescences from various organs. 
The new formations are not due either to a repe- 
tition or to a partition of any organ, but are out- 
erowths from others previously formed. 
In prolification and in multiplication the adven- 
titious structures are of independent origin. In fission 
the new developments grow simultaneously with the 
older ones, of which, indeed, they are mere repetitions. 
Moreover, in fission the supplementary lobes do not, 
in general, project in a plane different from that of 
the original structure, at least in the first instance, 
though their direction may ultimately become changed. 
_In enation the new growth projects from a previously 
formed organ after it has attained to considerable size, 
or even after its ordinary proportions have been attained, 
and it sprouts out from the beginning in a plane which 
is at a considerable angle to that of the parent organ, 
and it is sometimes of a different structure from it, 
and has different functions to fulfil. 
Many of the instances that occur of scales project- 
ing from petals, as in Caryophyllew, Sapindacee, &e., 
the coronal filaments of passion-flowers, the cup of 
Narcissus, the appendages that beset the segments of 
the perianth in Laliwm lancifoliwm, and other similar 
erowths, may be referred to a lke process. In many 
cases this has been proved by a study of the develop- 
ment of the flower, from which it appears that the 
erowths in question are developed subsequently to the 
formation of the ordinary floral whorls. It is requisite, 
however, to be cautious in pronouncing upon the exact 
