428 PHILOSOPHY OF ZOOLOGY. 



V. HYBKIDOUS ANIMALS. 



In the accomplishment of the important purpose of ge- 

 neration, it is observed, that, in the season of love, indivi- 



former method enjoyed an individuality distinct in its nature from the re- 

 sults of the latter, we are disposed to conclude, that it is a distinction 

 which has been incautiously adopted and which is apt to mislead. 



That many of the valuable cider and perry fruits of the seventeenth cen- 

 tury have already disappeared, parents and extensions, and, that some of 

 our present fruits are gradually wearing into decay, are facts which have 

 been satisfactorily established. But in order to account for these extinctions, 

 it is not necessary to admit, that all cuttings are limited in their duration to 

 the term of life of the parent from which they have been taken. The whole 

 phenomena seem simply to intimate, that extensions from a diseased parent, 

 are, in many cases, diseased likewise, and that the skill and industry of the 

 horticulturist cannot restore such to a healthy state. 



To have combated the assertion, that propagation by seeds is the only 

 true reproduction of plants, would have been unnecessary, had it not been 

 made by a deservedly celebrated botanist, whose authority, however, is 

 much greater in systematical than in physiological botany. That method of 

 reproduction in plants must surely be regarded as genuine, which is em- 

 ployed by Nature uniformly and extensively. 



In many cases, the multiplication of individuals takes place in the same 

 plant, both by extensions and seed. Among the herbaceous plants, many of 

 which are, in fact, annuals, the species of Orchis and Tulipamay be noticed. 

 Seeds are produced in these by the ordinary reproductive organs. At the 

 same time each individual, before closing its life of a year, prepares a de- 

 ccndent or bulb, which the following year supplies its place, when, perhaps, 

 not a single seed which it has produced has germinated. The continuance 

 of many species whose seeds germinate with difficulty, depends on these ra- 

 dical extensions or bulbs. Such natural extensions are not confined to the 

 monocotyledonous groups ; they occur in decotyledonous plants also ; and 

 among many of the acotyledonous tribes, there is no other natural method 

 of reproduction known. 



In other cases, where the continuance of the species could not be effected 

 by the ordinary methods of impregnation and the production of seeds, the 

 reproductive system furnishes bulbs, or extensions, to supply their place: 

 In the case of the vivijHtrous grutscs, the germs which arc to form the 



