336 HETEROMORPHY. 
wings. The fruit whilst young is pear-shaped, yellow, 
longitudinally striated and sweet; but, as it ripens, 
it becomes spherical, of a reddish-yellow, and bitter.” 
Sports or bud variations.—'l'hese curious departures from 
the normal form can only be mentioned mceidentally in 
this place, as they pertain more to variation than to 
malformation. 
The occasional production of shoots bearing leaves, 
flowers, or fruits of a different character from those 
found on the normal plant, is a fact of which gardeners 
have largely availed themselves in the cultivation of 
new varieties. The productions in question have been 
attributed to various causes, such as cross-breeding, 
grafting, budding, dissociation of hybrid characters, or 
reversion to some ancestral form, all of which expla- 
nations may be true in certain cases, but none of them 
supply the clue to the reason why one particular branch 
should be so affected, and the rest not; or why the 
same plant, at the same time, as often happens in 
Pelargoniums, should produce two, three, or more 
‘sports’ of a different character. 
These bud variations may be perpetuated by grafts 
or by cuttings, sometimes even by seed. With refer- 
ence to cuttings a curious circumstance has been 
observed, viz., that if taken from the lower part of 
the stem, near the root, the peculiarity is not trans- 
mitted, but the young plant reverts to the characters 
of the typical form (Carriere). This circumstance, 
however, is not of universal occurrence. 
For further particulars on this interesting subject 
the reader is referred to Darwin’s ‘ Variation of Ani- 
mals and Plants,’ i, p. 373, where numerous references 
are given, and wherein certain well-known and highly 
remarkable instances, such as the Cytisws Adan, the 
trifacial orange, &c., are discussed. 
