CHAP. CIII.

SAI.ICA'CEiE. SA I.IX.

1455

Hayne Dendr., as cited in Koch Comm. It seems that Koch ( 'Comm .) andLindley ( Synops. Brit. FI.) view the kinds of the group Purpureae whichhave only 1 stamen to a flower, as having that stamen constituted of 2 com-bined. Besides the kinds of that group treated of in our work, exclusively ofS. rubra, which may be examined as to the testing of this view, S. oppositi-fdlia of Host's Sal. Austr., i. t. 38.; S. austriaca Ibid., i. t. 64.; S. montanaIbid., i. t. 73. f. 5.; and S. monandra Ibid., i. t. 71., may also be inspected.

The Sexes. Botanists seem to differ in opinion, as to the influence whichthe sex has upon the character, or appearance, of the plants. Dr. Walkersays that “ the male and female, of the same species, often differ remarkablyfrom each other in their foliage;” and lie instances the S. alba L., in the femaleof which, he says, “ the leaves are much larger, greener, and not so white, sil-very, and pubescent, as those of the male. This makes the difference in theiraspect so great, he says, that, when standing together, they might, at first view,be presumed to be different species. In general,” he adds, “ the female of mostplants is of more vigorous growth, of larger size, and less brittle, than themale; and,” therefore, “the female ought always to be preferred when thespecies is to be cultivated for economical purposes that require strength; andthe male for those which require delicacy.” {Essays, p.420.) Sir J. E. Smithis of a very different opinion from Dr. Walker, asserting that between a maleand a female plant of the same species “ there is not the slightest possible dif-ference in the character or appearance of the two individuals, in any otherrespect” than in their flowers. {Eng. Flor., vol. iv. p. 163.) Most otherbotanists seem to incline more to the opinion of Dr. Walker, than to that ofSir J. E. Smith (see Hesfontaines’s Ilistoirc, &c., vol. ii. p. 460,; N. DuHam., vol. iii. p. 104., &c.); and it is only necessary to turn over the figuresof the splendid work of Host, in which engravings, a foot or two in length,are given of the male and female of every species, to be convinced that the viewtaken by Dr. Walker is correct. The importance, then, of knowing to whatsex any species of willow belongs that we intend to cultivate for use isobvious. It appears, also, from Dr. Host’s work, that the colour of theyoung wood, in the one sex, often differs from that of the other; forexample, the young shoots of S. alba, female, are not only stronger, and theleaves broader, than those of the male, but the bark is of a dark red; whilethe young wood of the male is of a whitish green.

Hybrids. The production of hybrids in this genus was observed by Sco-poli in 1760, and has since been confirmed or admitted by most other bota-nists. “ The great number of hybrids in this genus,” Koch observes, “noone can deny.” (p. 9.) Sir J. E. Smith, however, formed quite a differentopinion. During the thirty years that he studied the willows in Mr. Crowe’sgarden, along with that botanist, “ seedlings innumerable,” he says, “ springingup all over the ground, were never destroyed till their species were de-termined, and the immutability of each verified by our joint inspection. Thiswas the more material, to set aside the gratuitous suppositions of the mixtureof species, or the production of new or hybrid ones, of which, no more thanof any change in established species, I have never met with an instance.Strange alterations in the shapes and sizes of leaves, and their stipules, have,indeed, been seen on young radical shoots, from a tree or bush that has beenfelled; but not more than usually happens in poplars, limes, elms, andothers.” {Eng. FI., iv. p. 165.) It is much to be wished that some cultivatorof willows would endeavour to originate, scientifically, some hybrids betweenspecies with opposite characters of foliage, which would set this questionat rest.

Geography. The willows are chiefly natives of the colder parts of thetemperate regions of the northern hemisphere. They are generally found incold moist soil, or by water; the trees on plains, and the creeping or trailingsorts on heaths and mountains. A few species are natives of the arctic circle;and S. herbacea and S. arctica approach nearer to the pole than any other lig-neous plants. S. babyldnica is a native of Armenia, and also of China and Japan;

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