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ItOYAL HORTICULTURAL SOCIETY. 



lows, have a tolerably regular pollen, there is in hybrids of 8. 

 cinerea a marked irregularity which reaches its maximum in 8. 

 (cinerea +incana). While 8. caprea rather combines with 8. vimi- 

 nalis, Lapponum, and silesiaca, 8. aurita does so with 8. livida and 

 repens, and 8. cinerea, as 8. incana and purpurea, seems to occupy 

 a somewhat isolated position. 



We come now to the general conclusions. After first very 

 briefly stating Mr. Darwin's theory of the origin of species by 

 variation and elimination, our author proceeds to some general 

 consideration of hybrids. The habitual weakness, however, which 

 he supposes in males is not universal, though perhaps in every 

 male there is some weak point, however strong it may be in some 

 particulars. The hybrid then comes with no new peculiarities 

 into the world ; it has those of its parents, and generally in a 

 decidedly less complete degree. It is a perfect whole, so far as 

 the peculiarities of the parents agree with each other; so far, 

 however, as they differ it is intermediate, so that no speciality is 

 completely reproduced ; and since the differing parts are com- 

 bined in one intermediate whole, since these require different 

 conditions, the hybrid can never be perfectly accommodated to 

 outward circumstances*. A hybrid between a fish and a bird, 

 were such a creature possible, would never either swim or fly well 

 with its imperfect fins and feathers ; and something of the kind 

 must be the case with all males. We cannot, however, go so far 

 with the author as to say that no hybrid can be exactly fitted for 

 its place in nature, because, though it may not suit the circum- 

 stances of either of its parents, its intermediate nature may be 

 suited to some intermediate conditions, as species of different 

 climates form hybrids. 



As no two parent species agree entirely with each other, though 

 the hybrid may be equally strong with the parent as regards 

 one or more characters, there will always be characters in which 

 it is weaker, and therefore as a whole it will be less perfect. This 

 is quite the case with willows. 



The most imperfect simple hybrids are those which 8, viminalis 

 and 8. cinerea form with 8. triandra; and if we compare their 

 peculiarities, we find that they differ from each other more than 

 all other willows which form hybrids in free nature. 8. arluscula 

 an alpine willow of low stature, with the leafy stem of the catkin 

 is very different from 8. purpurea, a low-ground species. Th, 

 ,etificial hybrid between them is so imperfect, that it dies every 

 * This view is distinctly stated in Darwin, Or., p. 288, ed. 3. 



