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(Hybridity) Short Abstract

Journal de la Physiologies. Tom 2. 1859. Brown-Séquard.

Dr. P. Broca sur l' Hybridite (two parts in Vol I have preceded not read & 2 Parts in Vol. 3 not read.)

p. 219 Fertility of crosses only one character well put in discriminating species, well put.—

p. 223 cases of animals as Bull & mare uniting but never procreating.

p. 225. species easiest to unite not always produce the most fertile offspring.

p. 225. only one case of unequal "bilateral" & "unilateral" crosses, (better than my "reciprocal"

p. 227. offspring of unilateral crosses sometimes more fertile than of bilateral — Facility of crosses not necessarily related to their systematic affinity.—

p 231. In less fertile hybrids power of reciprocal crosses depends on individual more than on the species. Some relation betwen facility of first crosses & of fertility of their Hybrids

p. 232 doubt whether any cross betwen birds of very differnt incubation, Musk & common Duck is case. —

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p. 240 decries correctness of making class of mongrels— (very true in fact) as distinct from Hybrids. —

p 247. N. american Bison & cow, produce offspring fertile, if distinct families are crossed.—

254 no fixed law in resemblance of father & mother in Hybrids. —

255. on state of Spermatozoa in the Mule, sometimes present

257. Mule & Bardeau of unequal fertility

348 to 350 on crossed sheep & goats, very fertile: certain crosses used because fleece more valuable. —

353. conclusive facts on perfect fertility of dog & wolf, (but these not distinct)

360 good of on Guanaco & Alpaca crosses &c.—

362 on Anser-crosses

363 Canaries & Serin

365 Good remarks showing how impossible ever to get standard of evidence required by some authors.

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p 367. Morton speaks of "latent power of Hybridity." —

367 Famous Hare & rabbit case, supported by some fairly well previously established cases.

p. 376 - p 377 378 preponderant force of Rabbits in crosses.

— 381. apparently not [illeg] more variation in Hybrid progeny than in pure rabbits.

p. 382 3/8th rabbit blood have propagated for 10 generations Hybrids do Does not revert to either parent.

385. He well no remarks, that no one has proved that mongrel dogs indefinitely fertile yet admitted, — amplest evidence required on (p. 387) one side viz Hybridity & not on the other.

386. so overlooks selection & rate of breeding that he accounts for non-existence of races of mongrel curs by imagined sterility.

390. Wolves & dogs

p. 395 Jackall & dogs, (not distinct species C.D)

p 396 Foxes & dogs doubtful—