CHAP. CIII. AALICA V CEiE. .SA V LIX. 1455 



Haync Detidr., as cited in Koch Comm. It seems that Koch (Covwi.) and 

 Lindley (Synops. Brit. Fl.) view the kinds of the group Purpureas which 

 have 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 of 

 S. rubra, which may be examined as to the testing of this view, S. oppositi- 

 fdlia of Host's Sal. Austr., i. t. 38. j S. austriaca Ibid., i. t. 64.; S. montana 

 Ibid., 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 which 

 the sex has upon the character or appearance of the plants. Dr. Walker 

 says that " the male and female, of the same species, often differ remarkably 

 from each other in their foliage ;" and he instances the S. alba L., in the female 

 of which, he says, " the leaves are much larger, greener, and not so white 

 silvery, and pubescent, as those of the male. This makes the difference in their 

 aspect 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 most 

 plants is of more vigorous growth, of larger size, and less brittle, than the 

 male ; and," therefore, " the female ought always to be preferred when the 

 species is to be cultivated for economical purposes that require strength ; and 

 the male for those which require delicacy." {Essays, p. 420.) Sir J. E. Smith 

 is of a very different opinion from Dr. Walker, asserting that, between a male 

 and 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 other 

 respect" than in their flowers. (Eng. Flor., vol. iv. p. 163.) Most other 

 botanists seem to incline more to the opinion of Dr. Walker, than to that of 

 Sir J. E. Smith (see De&fontaines's Histoire, &c, vol. ii. p. 460. ; A T . Du 

 Ham., vol. iii. p. 104., &c.,) ; and it is only necessary to turn over the figures 

 of 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 view 

 taken by Dr. Walker is correct. The importance, then, of knowing to what 

 sex any species of willow belongs that we intend to cultivate for use is 

 obvious. It appears, also, from Dr. Host's work, that the colour of the 

 young wood, in the one sex, often differs from that of the other ; for example, 

 the young shoots of S. alba, female, are not only stronger, and the leaves 

 broader, than those of the male, but the bark is of a dark red ; while the 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, " no 

 one can deny." (p. 9.) Sir J. E. Smith, however, formed quite a different 

 opinion. During the thirty years that he studied the willows in Mr. Crowe's 

 garden, along with that botanist, " seedlings innumerable," he says, " springing 

 up all over the ground, were never destroyed till their species were de- 

 termined, and the immutability of each verified by our joint inspection. This 

 was the more material, to set aside the gratuitous suppositions of the mixture 

 of species, or the production of new or hybrid ones, of which, no more than 

 of 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 been 

 felled ; but not more than usually happens in poplars, limes, elms, and 

 others." (Eng. FL, iv. p. 165.) It is much to be wished that some cultivator 

 of willows would endeavour to originate, scientifically, some hybrids between 

 species with opposite characters of foliage, which would set this question 

 at rest. 



Geography. The willows are chiefly natives of the colder parts of the 

 temperate regions of the northern hemisphere. They are generally found in 

 cold moist soil, or by water; the trees on plains, and the creeping or trailing 

 sort 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. babylonica is a native of Armenia, and also of China and 



5 c 



