118 SYSTEMATIC BOTANY. 



slightly, but evidently, from the typical form ; the latter 

 may be smooth, and the individuals in question hairy; 

 the difference may be in the size of the plants, or in the 

 color of the flowers, shape of the leaves, or any other 

 minor character. If the descendants of these individuals 

 differ in the same respect from the typical form ; or, in other 

 words, if their characters are constant, they constitute a 

 variety of that species. Thus, one of the wild Buttercups 

 {Ranunculus aboHivus) has smooth, rather large stems ; but 

 a form of it (Ranunculus ahortivus, var. micranihu^') has 

 smaller, hairy stems. The cultivated Snow-ball is a variety 

 of the wild High Cranberry ( Viburnum Opulus) ; the 

 latter has only the outer flowers of the cluster enlarged 

 and conspicuous (neutral) ; in the former, they are all thus 

 characterized. The amount of variation, within varietal 

 limits, cannot of course be conventionally determined ; 

 some botanists may, in particular cases, call species what 

 others designate as merely good varieties. 



150. An individual of any species may occasionally 

 show a conspicuous variation from the typical form ; as, a 

 Violet without a spur, a Strawberry plant with simple 

 leaves, a regular flower, when the flowers of the plant are 

 labiate ; and so on. Such characters are not transmitted to 

 descendants; the latter present the typical form. Individ- 

 uals behaving in this manner are called sports. Exaggera- 

 tions of such tendencies often produce monstrosities. These 

 are sometimes instructive, especially in cases of reversion. 

 Thus in a monstrous flower, the several organs may revert 

 to the form of leaves, of which evidently, therefore, they 

 must be considered modifications; or a flower-bud may 

 develop into a branch, showing that the flower is homolo- 

 gous with the latter. The influence of cultivation (sub- 



