1 8 JOURNAL AND PROCEEDINGS 



an immense diversity of influences then must some of them have 

 been in contact with during their continuance in time and space, 

 and, if sensitive to these, what a diversity in size, form and color is 

 to be expected as a result. This helps to account for much of the 

 marvellous diversity which we actually do find in nature everywhere 

 around us. 



It is specially desirable to note here, that these influences 

 we have been considering, which accomplish the change in organisms, 

 are wholly external, acting from without, just as we saw that those 

 which make uniformity were internal, acting wholly from within. 



But there are several other influences at work in Nature pro- 

 ducing variety in organisms, some of which we as yet know little or 

 nothing about, hence the expression, "accidental variation." But 

 as accident is not recognized in science, every effect having unques- 

 tionably an efficient cause, whether within the range of our ken or 

 no, I prefer " individual variation " to express the idea associated with 

 these peculiarities that unexpectedly show themselves, and which are 

 often seized upon by breeders for the improvement of stock, and for 

 the production of fancy and ornamental forms. This has been 

 carried to an astonishing length in some departments, and these 

 varieties may appear in Nature as well. 



Here then the question arises, do these variations, by what- 

 ever cause produced, or by whatever name called, going off in oppo- 

 site directions, ever attain a point of complete separation : that is, 

 when individuals that have come from a common stock are brought 

 together from the extremes of unlike, will Nature in them fail to 

 acknowledge their original relationship. Consideration is required 

 here. We know that many animals go in flocks, herds, coveys, 

 swarms, &c, and that each of these aggregations incline to keep by 

 themselves, and do not readily mingle in Nature ; that an individual 

 from one of these will be refused admission into another of the 

 same kind, and can only obtain it by conquering a position. This 

 we see frequently amongst domestic animals, and if the external 

 forms are diverse the trouble is all the greater, so that it may 

 require time, restraint, compulsion even, to get them at first to live 

 together. This being accomplished, all our information goes to 

 prove that no matter what external difference separates them, inter- 

 nally they are yet one. Mr. Tegetmeyer, the celebrated writer on 

 poultry, when describing how he had bred the golden, the silver and 



