periosteum of a dog producing bone in, ii. [369].

Race-horse, origin of, i. 54.

Races, modification and formation of, by crossing, ii. [95]-[99];

natural and artificial, ii. [245];

Pouchet's views on plurality of, i. 2;

of pigeons, i. 207-212.

Radishes, i. 326; crossing of, ii. [90];

varieties of, ii. [217]-[218].

Radclyffe, W. F., effect of climate and soil on strawberries, i. 354;

constitutional differences in roses, i. 367.