iae at the base of the standard petal,
hairiness of the ovarium, and in almost every other character, between _C.
laburnum_ and _alpinus_; but it approaches the former species more nearly
in colour, and exceeds it in the length of the racemes. We have before seen
that 20.3 per cent. of its pollen-grains are ill-formed and worthless. My
plant, though growing not above thirty or forty yards from both
parent-species, during some seasons yielded no good seeds; but in 1866 it
was unusually fertile, and its long racemes produced from one to
occasionally even four pods. Many of the pods contained no good seeds, but
generally they contained a single apparently good seed, sometimes two, and
in one case three seeds. Some of the seeds germinated.

[907] 'Annales de la Soc. de Hort. de Paris,' tom. vii., 1830, p. 93.

[908] 'Annals and Mag. of Nat. Hist.,' March, 1848.

[909] 'Pomologie Physiolog.,' 1830, p. 126.

[910] Gallesio, 'Gli Agrumi dei Giard. Bot. Agrar. di Firenze,' 1839, p.
11. In his 'Traite du Citrus,' 1811, p. 146, he speaks as if the compound
fruit consisted in part of lemons, but this apparently was a mistake.

[911] 'Gard. Chron.,' 1855, p. 628. _See_ also Prof. Caspary, in 'Transact.
Hort. Congress of Amsterdam,' 1865.

[912] 'Gard. Chron.,' 1851, p. 406.

[913] Gaertner, 'Bastarderzeugung,' s. 549. It is, however, doubtful whether
these plants should be ranked as species or varieties.

[914] Gaertner, idem, s. 550.

[915] 'Journal de Physique,' tom. xxiii., 1783, p. 100. 'Act. Acad. St.
Petersburgh,' 1781, part i. p. 249.

[916] 'Nouvelles Archives du Museum,' tom. i. p. 49.

[917] L'Hermes, Jan. 14, 1837, quoted in Loudon's 'Gard. Mag.,' vol. xiii.
p. 230.

[918] 'Comptes Rendus,' tom. xxxiv., 1852, p. 746.

[919] 'Geograph. Bot. de l'Europe,' tom. iii., 1854, p. 405; and 'De la
Fecondation,' 1862, p. 302.

[920] 'Traite du Citrus,' 1811, p. 45.

[921] 'Transact. Linn. Soc.,' vol. ix. p. 268.

[922] Gaertner ('Bastarderzeugung,' s. 611) gives many references on this
subject.

[923] A nearly similar account was given by Bradley, in 1724, in his
'Treatise on Husbandry,' vol. i. p. 199.

[924] Loudon's 'Arboretum,' vol. iv. p. 2595.

[925] 'Bastarderzeugung,' s. 619.

[926] Amsterdam, 1768, p. 124.

[927] 'Gard. Chron.,' 1860, p. 672, with a woodcut.

[928] 'Philosophical Transact.,' vol. xiiii., 1744-45, p. 525.

[929] Mr. Swayne, in 'Transact. Hort. Soc.,' vol. v. p. 234; and Gaertner