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(a) Animal Hybrids

We have as yet considered only Plants. Laws of propagation seem very similar (Scarcely anything know beyond the Vertebrata) — But far less Known about animals. Mental qualities come into play.

It has been said revulsion. — Hardly any evidence, animals of same species take fancies. (Dovecot pigeons do not readily associate with fancy breed, sheep in certain isld.)— This under vars.) But so far from revulsion that in many great groups of animals, almost as many crosses have taken place as fresh marriages.

To give an idea of how many crosses have been effected tabulate Gallinaceous & Duck tribes. Ruminates.— XX Just as in plants some tribes cross more readily than others.

It is really hardly too much to say that species cross as readily as pure species bred in Menageries

[in margin:] The several cases of crosses wild in animals, hereafter to be enumerated shows no revulsion.— Perhaps sum up cases even genera.

(A X) The conclusion I shd. draw was that species of the higher Vertebrata cross more readily than plants, & with a greater range of systematic (& constitutional differences) — evident wide differs plants. Hence even genera cross almost in state of nature but resultant Hybrids considerably more sterile. (xx) Cases of absorption have taken place (?) — 2 Pheasants versicolor hybrid crossed with pure versicolor provided birds indistinguishable from pure.— Triple crosses.—

Hybrids have often bred with either pure parent. Hybrids themselves very few cases. Pheasants of Andrew Smith pheasants & Fowls & Geese of Eyton & of Blyth.

A X Here conclusion.

With respect to perfect fertility of any two species or of the resultant Hybrids, I know of no case universally admitted.— (Anser cygnoides & cinereus). ─Excepting so far as dogs & cattle are thought to be descended from different

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These references useful for final discussion

Reciprocal crosses not being usually (!) alike one of most striking differences from plants

Compare with some remark on similarity of laws of propagation, throughout both great Kingdoms organic bodies.

Gærtner Bastardz p. 136 cases of some Hybrids Dogs, deer &c. Ram mate with Mouflon &c

— p 231. Attributes great importance to sex of animal in crossing — but the difference in sexes of Donkey & Horse very slight, not enough I shd think, to account for difference. It cannot be owing to sexual secondary character, but yet to sex.—

Gærtner p. 264 Description of influence of male & female in animals & plants, with references — 340 X quote case to show male side fails more than female. in animals as in plants

— p 381. on mule's (female) breeding in hot country — on Black swan, breeding with white, (Alector & Crex, Morton)

p 382 male hybrid pheasant—sterile.—

Kolreuter 2d Fort. Preface p. 8 case of Canary & Linnet fertile in 5 generation per Matem or Canary Bird

[sketch]

Wiegman ueber die Bastarderzeugung p. 21 —description of hybrid wolf-hound.

Herbert. Amaryll. p. 339. Hybrid fox

Mem. I remember Black Guinea Black Grouse & Pheasant have crossed free reciprocally. —