BOTANY. 377 



than the wild stock; it accordingly tends, not only to (lcyc-ncratr<. (as the culti- 

 vator would term it) towards its original and less useful state, but also to 

 sport into new deviations, in various directions, with a freedom and facility 

 not manifested l>y its wild ancestors. This explains the readiness with 

 which we continually obtain new varieties of those esculent plants which 

 have been a long time in cultivation, while a newly-introduced plant exhibits 

 little flexibility. To detect the earliest indications of sporting, and to select 

 for the parents of the new race those individuals which begin to vary in the 

 requisite direction, is the part of the scientific cultivator. In this way, the 

 elder Vilmorin succeeded in producing the esculent carrot from the wild 

 stock in the course of three generations, no addition to our resources, 

 indeed, but significant of what may be done by art directed by science. B} r 

 adopting and skilfully applying these principles, the younger Vilmorin has 

 conferred a benefit upon France which (if she will continue to make sugar 

 from the beet) may almost be compared with that of causing two blades of 

 grass to grow where only one grew before, having, so to say, created a race of 

 beets containing twice as much sugar as their ancestors, and indicated the 

 practicability of its perpetuation. The mode of procedure, and the ingeni- 

 ous methods he contrived for rapidly selecting the most saccharine out of a 

 whole crop of beets, as seed-bearers for the next season, are detailed in these 

 papers. 



Once originated, and established by selection and segregation for a few 

 generations, the race becomes fixed and perpetuable in cultivation, with 

 proper care against intermixture, in virtue of the most fundamental of or- 

 ganic laws, viz., that the offspring shall inherit the charactei'istics of the 

 parent, of which law that of the general permanence of species is one of 

 the consequences. The desideratum in the production of a race is, how to 

 initiate the deviation. The divellant force, or idiosyncracy, the source of 

 that " infinite variety in unity which characterizes the works of the Crea- 

 tor," though ever active in all organisms, is commonly limited in its practical 

 results to the production of those slighter differences which ensure that no 

 two descendants of the same parent shall be just alike, being overborne by 

 that opposite or centripetal force, whatever it be, of which ensures the partic- 

 ular resemblance of offspring to parents. Now, the latter force, as Mr. Louis 

 Yiimorin has well remarked, is really an aggregation offerees, composed of 

 the individual attraction of a series of ancestors, which we may regard as the 

 attraction of the type of the species, and which we perceive is generally all- 

 powerful. There is also the attraction or influence of the immediate parent, 

 less powerful than the aggregate of the ancestry, but more close, which ever 

 tends to impress upon the offspring all the parental peculiarities. So, when 

 the parent has no salient individual characteristics, both the longer and the 

 shorter lines of force arc parallel, and combine to produce the same result. 

 But whenever the immediate parent deviates from the type, its influence 

 upon its offspring is no longer parallel with that of the ancestry; so the 

 tendency of the offspring to vary no longer radiates around the type of the 

 species as its centre, but around some point upon the line which represents 

 the amount of its deviation from the type. Left to themselves, as Mr. Vil- 

 morin proceeds to remark, such varieties mostly perish in the vast number 

 of individuals which annually disappear, or else, we may add, are obliter- 

 ated in the next generation through cross-fertilization by pollen of the sur- 

 rounding individuals of the typical sort, whence results the general fixity 

 of species in nature. But under man's protecting care they are preserved 



32* 



