84 TIG EONS. 



enforced, would plunge all animated matter into indescribable 

 confusion, that the offspring produced by the intercourse of 

 different, (that is, distinct species,) is incapable of further 

 increase. That such an intercourse may be effected, is \\vll 

 known; but it is generally under peculiar or artificial circum- 

 stances, and rarely when the animals, birds, or whatever they 

 may be, are in their natural state, and in a condition to make 

 their own election. Thus it is in the crosses obtained in a 

 state of confinement, between the Canary and goldfinch, 

 linnet, &c. But in all these instances, the progeny are 

 invariably "mules," and as a general rule, are incapable of 

 further production; for although they may exhibit the passions 

 natural to the sexes, and the females may produce eggs, 

 which, in general, even with extreme care, are found addled 

 and incapable of being hatched. Such, I may add, is the case 

 with hybrids of some of the crosses themselves ; for the mongrel 

 progeny of the wild turtle dove, (Tur/ur communis,*) of Europe, 

 with the turtle of the aviary, (T. risoria,") has jeen proved, by 

 frequent experiments, to be barren, although the two species 

 whence it originated appear to be closely allied, and a mixed 

 breed is easily procured; and such I am justified in saying, 

 would be the event, if a cross could be obtained between the 

 rock pigeon, (Columba lima,) and the European wood pigeon, 

 (C. anas,) or stock dove, as it is improperly called, or with the 

 ring pigeon, (C. palumbus,) or any other species. 



VARIETIES. 



To describe or particularise all the varieties possessed by 

 fanciers, would require a volume in itself; as, in addition to the 

 permai,ent races, or those which, when kept pure, transmit 

 their likeness to their offspring, there are intermediate casts 

 produced by particular crosses between individuals belonging 

 to the different varieties, and which, though h'ghly prized in 

 the first generation, are not considered v- >rthy of further 

 extension ; as their progeny cannot be depended upon, but are 



