1456 ARBORETUM AND FRUTICETUM. PART III, 
and Royle mentions several species as indigenous both to the lowlands and 
mountainous regions of Northern India. 8. pedicellata Desf. and S. baby- 
lénica are found wild in the north of Africa; and §. Humboldtidna and 
S. Bonplandidxa on the mountains of Peru and Columbia. The species 
indigenous to North America are not very numerous; but Pursh has de- 
scribed 37 sorts, as either wild or in a state of cultivation there. The 
number of species in different countries, however, cannot at present be deter- 
mined with anything like accuracy, since what are considered as species by 
some botanists are looked upon as only varieties by others. Thus, Schleicher 
finds 119 species within the narrow limits of Switzerland; Host, 60 species 
natives of Austria; and Smith, and other British botanists, 71 species in- 
digenous to Britain. Koch, however, the latest, and, as it appears to us, the 
most judicious, writer on the genus Salix, considers that all the alleged spe- 
cies, natives of Europe, may be reduced to 48. Perhaps, in addition to 
these, there may be a dozen natives of North America, which are not natives 
of Europe; and half that number natives of Asia. Of 182 species described 
by botanists, Koch observes, 17 only are extra-European. 
History. Theophrastus and Pliny speak of different sorts of willows; the 
latter describing 8 species, as among the most useful of aquatic trees, not even 
excepting the poplar and the alder. The willow, Pliny says, furnishes long 
props for supporting vines, and the bark may be employed for tying up the 
shoots; and the young shoots, he adds, are much employed in basket-making. 
The kinds which the Romans used for this purpose appear, from Pliny’s 
descriptions, to have been the S. alba, S. vitellina, 8. viminalis, and the S.ame- 
rina of Pliny and Dalechamp, which was probably, as Dr. Walker thinks, the 
white willow of Theophrastus, and is certainly the S. decipiens LZ. These 
kinds formed the osier holts of the Romans, and are still those principally 
cultivated for basket-making, throughout Europe and North America, in the 
present day. Among modern botanists, the Bauhins, in 1650, first began to 
distinguish willows by their magnitude, the shape of their leaves, and by the 
nature of their flowers and fruit: and these authors were also the first to 
recognise in each species a fertile and an unfertile individual; and, with 
Tragus, to assert that willows could be propagated from seed, like other plants; 
a fact that had been denied since the days of Aristotle. Scopoli, in his 
Flora Carniolica, published in 1760, relates that he had often observed female 
willows fecundated by males which are accounted of a different species; and, 
if this observation is correct, it will help to account for the great number of 
kinds which compose this genus. The scientific botanical history of the wil- 
low may be considered as commencing with Ray’s Synopsis, in 1660, in which 
he describes 10 species as growing in the neighbourhood of Cambridge. _Lin- 
nzus, in 1737, described, in the Flora Lapponica, 19 species, chiefly alpine 
kinds ; and in the second edition of his Species Plantarum, published in 1753, 31 
species. Haller, in 1758, described 21 species as natives of Switzerland ; and 
Villars, in 1789, 30 species as natives of Dauphiné. Willdenow, in his edition 
of Linneeus’s Species Plantarum, published in 1797, describes 116 species. 
Smith, in Rees’s Cyclopedia, published in 1819, describes 141 species; to which 
Willdenow and other botanists have since added, according to Koch, 41 species 
more, making in all 182; adding to these Schleicher’s 119 new species, the 
total number is 254! In 1785, Hoffmann published the first fasciculus of his 
elaborate History of Willows, the last fasciculus of which came out in 1791; 
but the work was never completed. In so far as it goes, it is a splendid work ; 
and one which can scarcely be surpassed either for accuracy or beauty. In 
1828, Professor Koch, director of the botanic garden at Erlangen, published 
his De Salicibus Europeis Commentatio, an admirable work, of which a more 
particular account will be given here after; in which he has reduced all the 
European sorts, amounting, as we have just seen, to 237 (17 of the 254 being 
extra-European), to 48 species, belonging to 10 groups. Subsequently to the 
appearance of Koch’s work, Dr. Host, director of the Flora Austriaca Botanic 
Garden at Vienna, published his Salix; of which only the first volume ap- 
