98 HYBRIDISING AND CROSS-BREEDING. 



cases no information beyond that afforded by an examination 

 of the plant before him, and it is impossible to find any definite 

 distinction between hybrids and species, even after the closest 

 examination possible; and many hybrid plants, such as Del- 

 phinium formosum, Primula elatior, and others, reproduce them- 

 selves from seed as exactly as, or even more so than, many 

 pure species or plants generally received as such. Indeed 

 some varieties, and notably Pelargonium " Christine" and P. 

 "Madame Vaucher" and the races of Greengages and Dam- 

 sons among Plums, reproduce themselves from seed with but 

 little variation. Just as species and varieties are in many cases 

 undistinguishable by structural or functional characteristics, so 

 are bud variations or "sports" often so permanent and distinct 

 as to be perfectly unrecognisable from seminal varieties; in- 

 deed it is often assumed that sports and seminal variations have 

 a common causation in the uniting of two sets of individual 

 characteristics by hybridisation or cross-breeding, only in the 

 latter case the variation is apparent from the time of the germi- 

 nation of the seed, while in the former the blended characters 

 are not apparent until after the plant has grown considerably. 



In the 'Proceedings of the Royal Society,' 1872, Mr 

 Francis Galton has a valuable paper on " Blood Relationship," 

 from which we learn that every individual parent animal (and 

 we may add plant) transmits, or has the power to transmit, to 

 its progeny qualities and variations which are latent in itself, 

 but which may become apparent in the offspring from the first ; 

 or, owing to some cause of which we are unaware, these latent 

 and previously unsuspected qualities break out in the indi- 

 vidual in the form of sports. Thus every adult human being 

 and every perfect plant is composed of two sets of characters, 

 the one apparent, the other latent; and both of these are 

 combined in the primary stage, having been inherited, and they 

 are both again combined in the progeny. There are, however, 

 two parents, and what is true of the male is true also of the 

 female ; and it is thus made evident that the primary or germinal 

 vesicle stage, although apparently a simple one, is really more 

 complicated than the adult or perfect form, for in the germinal 

 vesicle and embryo are condensed the united latent and per- 

 sonal or evident characters of both parents. The multiplica- 

 tion of characteristics in individuals would thus go on in pro- 

 gression, were it not that the weaker characteristics are crowded 

 out or rendered latent by the stronger ones in all well-organised 

 progeny. 



The physiologist is as uncertain as the practical cultivator as 

 to the causation or origin of these variations : they are never- 



