CHAP. CXIII.

coni'feiue. abie'tjn.®:.

2151

the cones of all the varieties of P. sylvestris terminate in surfaces havingmore or less the appearance of a depressed pyramid; those of all the varietiesof P. Laricio have a smooth lip, more or less protruding, and terminatingin a depressed point; those of all the varieties of P. Pinaster terminate ina strong woody pyramidal point; and those of all the varieties of P. Pae'dain a slender sharp prickle, turned upwards or downwards. The cones ofdifferent varieties of what we consider as the same species vary much insize; and, as these variously sized cones are generally reproduced fromseed, the plants bearing them have been usually treated as distinct spe-cies. We do not, however, consider the fact of the seed of large-conedvarieties producing plants bearing large cones, any more a proof that the kindis a species, than we do that of seedlings from the seeds of a large apple pro-ducing trees bearing large apples, a proof that the particular kind of apple isa species distinct,from apple trees bearing small apples. The cones of P.(s.) p.Mughm are twice the size of those of P. (s.) p. pumilio; but in other respectsthe plants are hardly distinguishable. Perhaps we shall be told that the com-parison between pine trees and apple trees is not a fair ground of argument;because the apple tree is in a state of culture, and far removed from its naturalhabits; but to this we answer, that the same effects as those produced byculture in the apple tree, are produced by a variety of geographical and phy-sical circumstances in the pine tree; and of this the two above-namedvarieties of P. sylvestris may be cited as a proof.

The leaves of all the species of pines may be classed according to the num-ber in a sheath; and this is a most convenient mode of determining the groupsand even the species, in the case both of young plants, and of trees withoutcones. All the European species, with the exception of P. Cembra , have onlyCleaves in a sheath, and most of the Asiatic, Mexican, and Californian kindshave C 4, or 5 leaves ; while those of the United States and Canada have, forthe moa„ part, 3. The leaves vary in length in different species; but much lessso in the varieties of the same species than might be imagined. Thus, in allthe varieties of P. Laricio the leaves are nearly double the length of those of■P. sylvestris .

Pinus . In studying this genus, and arranging the kinds according to theirWs, cones, and leaves, we consider P. sylvestris , P. Laricio, P. Pinaster,**• Pinea, P. halepdnsis, and P. Cembra , as the principle European species, andthe other European kinds as only varieties of them. P. australis, P. Pae'da,V Banksidna, P. inops, P. pungens, and P. Atrobus, we consider as the prin-C1 pal species of North America . P. Sabin iana, P. ponderosa, and P. insigniaare the principal species of California . P. Lambertiarea and P. monticolaalso from California, and P. excelsa from Nepal , appear to be only varieties°,/*■ Strobus. The most remarkable species from Nepal is P. Gerardiana,''jhicli has straight stiff leaves like those of P. Pinea, but with caducous

^ hies is a genus of which there are so few species, that it is attended withno great difficulty. A. rubra, A. nigra, and A. alba are probably only differ-*t forms of one and the same species. A. Smithiana may possibly be a variety0 A. excelsa, and A. dumosa of A. canadensis. A. Douglas! and A. Menziesii.appear specifically distinct, but there are only very small plants of the latterhois country. One of the most remarkable species of A' bies, from Cepha-n ! a > which has lanceolate and sharp-pointed leaves, like those of an arau-a^a, has just (1837) been introduced.

, lcea is a very easy genus ; P. balsamea, Fraser!, and Pichta are probably only, ne !; les °f one species; and, though P. Webbtdna has purple cones, we doubte ™ r h can be considered more distinct from P. pectinata than Pilia| Mdifbfia is from T. parvifolia. The colour of the cones in the Abietinaesiy n ° c ^ a ' m to be considered a specific distinction; because in all exten-e woods of one species, such as of P. sylvestris and Larix europae'a in“dancb they will be found to vary considerably.

' anx> It appears very doubtful to us, whether there are more than one