lU) THE GENESIS OF SPECIES [Chap. 



development of species witli a luany fticetted spheroid 

 tuni1)ling over from one facet, or stable ecpiilibrinm, to 

 another. The existence of internal conditions in animals 

 corresponding with such facets is denied l»y [)ure Dar- 

 winians, but it is contended in this work, though not in 

 this chapter, that something may also be said for their 

 existence. 



The considerations brought forward in the last two 

 chapters, namely, the difficulties with regard to incipient 

 and closely similar structures respectively, together with 

 palitontological considerations to be noticed later, appear to 

 point strongly in the direction of sudden and considerable 

 ehanges. This is notably the case as regards tlie young 

 oysters already mentioned, which were taken from the 

 shores of England and placed in the Mediterranean, and 

 which at once altered their mode of growth and formed 

 prominent diverging rays, like those of the fro][>er Mediter- 

 ranean oyster ; as also the twenty-nine kinds of American 

 trees, all differing from their nearest European allies simi- 

 larhj — " leaves less toothed, buds and seeds smaller, fewer 

 branchlets," &c. To these may be added other facts given 

 by Mr. 1 )arwin. Thus he says " that climate, to a certain 

 extent, directly modifies the form of do^s." ^ 



The Eev. R. P2verett found that setters at Delhi, though 

 most carefully ])aired, yet had young with " nostrils more 

 contracted, noses more pointed, size inferior, and lind)S 

 more slender." Again, cats at ^lonibas, on the coast of 

 Africa, have short stiff hairs instead of fur; and a cat at 

 Algoa Bay, when left only eight weeks at ]Mombas, " \inder- 

 went a complete metamor[)hosis, having parted with its 



^ "Animals and I'laiit.s untk-r Domestication," vo]. i. p. 37. 



