black-seeded, antiquity of, ii. [429].
Porcupine, breeding of, in captivity, ii. [152].
Porcupine family, ii. [4], [76].
Porphyrio, breeding of a species of, in captivity, ii. [156].
Portal, on a peculiar hereditary affection of the eye, ii. [9].
Porto Santo, feral rabbits of, i. 112.
Potamochœrus penicillatus, ii. [150].
Potato, i. 330-331;
bud-variation by tubers in the, i. 384-385;
graft-hybrid of, by union of half-tubers, i. 395;