OIL-GLAND, absence of, in fantail pigeons.

OLDFIELD, Mr., estimation of European dogs among the natives of Australia.

OLEANDER, stock affected by grafting in the.

OLLIER, Dr., insertion of the periosteum of a dog beneath the skin of a rabbit.

Oncidium, reproduction of.

ONIONS, crossing of. -white, liable to the attacks of fungi and disease.

Ophrys apifera, self-fertilisation of. -formation of pollen by a petal in.

Opuntia leucotricha.

ORANGE. -crossing of. -with the lemon. -naturalisation of, in Italy. -variation of, in North Italy. -peculiar variety of. -bizzarria. -trifacial.

ORCHIDS, reproduction of.