116 Extracts from the Journals. [July, 



consequences; for we can readily believe that they might follow 

 where the parents were not at all connected by consanguinity. 

 The animals might belong to families wholly distinct, and yet 

 their hereditary tendencies be similar. For example: let there 

 be chosen a bull and cow wholly unrelated, or even of different 

 breeds, each of which has disease of the liver to the same degree, 

 and each also an equal hereditaiy tendency to that disease; the 

 progeny generated by two such animals would no doubt have the 

 same predisposition to the defect or disease of the parent as if 

 both the latter had been of the same family. Thus the degene- 

 racy of offspring is not owing to the relationship, simplv, but to 

 the natural defects of the parents or ancestors. The skillful breed- 

 er will therefore select his animals for propagation with a view 

 of avoiding defects and increasing excellencies in the progeny. 



But it may be said that excellencies as well as defects are 

 transmissable hereditarily; and as animals of near relationship 

 are sometimes found which possess certain valuable qualities in a 

 greater deo;ree than they are to be found elsewhere, the question 

 is suggested — Why not permit these animals to breed together? 

 This we should be in favor of to a certain extent; but the ani- 

 mals should be selected with judgment, and with particular care 

 that they have not a predisposition to important defects. It will 

 not do to rely on the idea that their good points will overpower 

 their bad ones; for as their superior points or qualities are proba- 

 bly the result of art or accident, (not being natural or common to 

 the race.) their defects will be more likely to be increased in the 

 progeny than their excellencies.* 



The remark in relation to animals which exhibit peculiarities 

 not common to the race, we will endeavor to illustrate. For in- 

 stance, in a species of squirrels, the general color of which is grey, 

 we now and then find those which are perfectly white. Similar 

 deviations from the general color of the species are met with also 

 in mice, and other animals. The same thing is found in birds. 

 We have heard of crows which were nearly white,f and we have 



•Sebright observes Ihal — " If one male and one female only of a valuable 

 breed eonM be obtained, the offspring should be separated, and placed in situ- 

 ations as dissimilar as possible ; for animals kept together are all subjected to 

 the eflects of the same climate, of the same food, and the same mode of treat- 

 ment, and consequently to tlie same diseases, particularly to such as are in- 

 fectious, which must accelerate the effects ofbreeding inand-in. By estab- 

 lishing the breed in different places, and by selecting with a view to obtain 

 different properties in these several colonies, we may perhaps be enabled to 

 continue tlie breed for some lime, without the intermixture of other blood. 



t White Crows. — In an article on the " Principles of Breeeding," in another 

 part of this number, it is liienlionpd that white crows have been sometimes 

 seen Since that article was written, we have learned, through the Zanes- 

 ville, (0.) Gazette, that Dr. W. E. Ide, of that place, has lately received for 

 his ornithological cabinet, one of these rare birds, which was shot in that vi- 



