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temple. The Cypress (also called Cedar by the ancients,) the Pinus Halepensis, and the tall fragrant Juniperus of the Lebanon, with its fine red heart-wood, would have been far more prized on every account.

On the other hand, that the grove has, within the historic period, increased and diminished in extent, owing to secular changes in the climate, cannot be doubted, when it is remembered, that no seedling has come to maturity (though thousands annually germinate), since the birth of trees the youngest of which is 18 inches in girth; and that the whole grove presents such a disparity in the ages of its trees, that only about 15 exceed as many feet in girth, and 385 fall below 12 feet girth. Upon this point I have collected some curious corroborative evidence, from the works of old travellers.

The nearest point to the Lebanon at which Cedars have been found, is the Bulgar-dagh chain of the Taurus in Asia Minor, and from that point forests extend eastward to Pisidia, in long. E. 320, westward to long. E. 36°, and northward to the Anti-Taurus, in lat. 40° N.; growing at elevations of 4000 to 6400 feet above the sea. The Lebanon may

be regarded as a branch of the Taurus, and is 250 miles distant from the Cedar forests upon that chain. Between individuals from the Lebanon, and the common Asia Minor form, there is said to be no appreciable difference, by those who have examined both: but there are two distinct forms or varieties in the latter country; one having shorter, more stiff and glaucous or silvery foliage than the other; this is the Silver-cedar, C. argentea, of our gardens. Northern Syria and Asia Minor form one botanical province; so that the Lebanon grove, though so widely disconnected from the Taurus forests, can be regarded in no other light than as an outlying member of the latter.

C. Atlantica. At a distance of 1400 miles from the Cedar forests of Asia Minor, and separated by the whole breadth of the Mediterranean sea, are those of Algeria. These form the prevalent arboreous vegetation throughout the eastern province of Constantine, which borders on Tunis, and they also abound on the eastern Atlas ranges; though whether they extend to the greater Atlas and into the kingdom of Morocco is not known. They characterize the upper mountain zone (5200-7200 feet), and approach within twenty miles of the sea. The African Cedar differs from that of Lebanon in having a perfectly erect, rigid leader, and straight stiff ends to the branches, all which, in the Lebanon plant, droop more or less. In the African, the cone is generally smaller, the leaves shorter and more glaucous, and the scales and seeds triangular in form (instead of quadrangular.) There are two forms of Cedar in Algeria, as in Taurus, and characterized by the same differences in each country, viz.: a greener longerleaved, and a more silvery shorter-leaved variety. Nevertheless it is generally easy to distinguish the Atlas Cedar from the Lebanon one, and in beds of young plants the differences are very marked, though it is always possible to pick out deceptive specimens.

C. Deodara. Proceeding eastward from the Lebanon, we come, after another 1400 miles, to the Cedar forests of Affghanistan, which extend thence continuously eastward along the Himalaya, almost to the confines of Nepal. The Cedrus Deodara is in India exclusively a western tree; it begins where the influence of the monsoons is much diminished, that is, where the climate begins to approximate to that of the Levant. It inhabits various elevations between 4,000 and 12,000 feet, and in Affghanistan outnumbers all other Pines in abundance of individuals. The C. Deodara has a much more pendulous leader and ends to its branches, and longer leaves, of a more glaucous hue, than C. Libani, though not such silvery leaves as the C. Atlantica. The cones are as large as those of C. Libani, but the scales and seeds are of the same form as those of C. Atlantica, and hence markedly different from those of C. Libani.

From what has been said respecting each of these Cedars, it is evident, that the distinctions between them are so trifling, and so far within the proved limits of variation of Coniferous plants, that it may reasonably be assumed that all originally sprang from one. It should be added, that there are no other distinctions whatever between them-of bark, wood, leaves, male-cones, anthers, or the structure of these-nor in their mode of germination or duration, the girth they attain, or their hardiness.* Also, that all are very variable in habit; so much so, indeed, is this the case with the Deodar, which is the most distinct of all in habit, that though it was not introduced much more than thirty years ago, there are already five distinct varieties sold by nurserymen, some as stiff, others as dark-coloured, and others as short-leaved as the Lebanon Cedar. Also, that though the difference in the shape of the scales and seeds of Deodara and Libani are very marked, they vary much; many forms of each overlap; and further transitions between the most dissimilar, may be established by intercalation of seeds and scales from C. Atlantica.

To render these distinctions more clear, I have had drawings of the three Cedars made from native and cultivated specimens, selected by Professor Oliver and myself from the Herbarium and Museum at Kew, and which represent what we believe to be the most decided characters that they severally present; and that these are both faithful and characteristic portraits, Mr. Fitch's name is sufficient guarantee. They represent, in each case, the fully formed cone, and the same on the eve of bursting; the average and extreme forms of scales and seeds, the anthers, the foliage, and the extreme and mean lengths of the leaves.

Hitherto, C. Atlantica has been almost universally considered a

The assumed distinctive characters between the Deodar and Lebanon Cedar that were founded on the form of the cones, the falling away of their scales, the shape of the leaf in section, the wood, its odour and durability, have all been satisfactorily disproved long ago.

variety of Libani, and C. Deodara a different species; habit having been relied upon exclusively, and botanical characters neglected; for a glance at the drawings shows that there is an obvious and marked difference, in the latter respect, between the common states of Atlantica and Libani, and none between Atlantica and Deodara. This is perplexing, for, as I have said above, C. Libani holds an intermediate position, both geographically and in characters of foliage, between the two that agree in the most important characters: and further, we can account, in a great measure, for the differences of habit, by the climate of the three localities; the most sparse, weeping, long-leaved Cedar is from the most humid region, the Himalaya; whilst the plant of most rigid and otherwise opposite habit, corresponds with the climate of the country under the influence of the great Sahara desert. No course remains, then, but to regard all as species, or all as varieties, or the Deodara and Atlantica as varieties of one species, and Libani as another. The hitherto adopted and only alternative, of regarding Libani and Atlantica as varieties, and Deodara as a species, must be given up.

I have dwelt thus at length upon the value of the characters separating the three Cedars, because the question, whether these are one species or three, stands at the threshold of all inquiry into the early history of the plant. My own impression is, that they should be regarded as three well-marked forms, which are usually very distinct, but which often graduate into one another, not as colours do by blend ing; but as members of a family do, by the presence in each of some characters common to most of the others, and which do not interfere with or obliterate all the individual features of their possessor. Moreover, I regard them as in so far permanently distinct plants, that though all sprang from one parent, none of them will ever assume all the characters either of that extinct parent or of the other two forms. There will, in short, be no absolute reversion amongst these. Each will yield varieties after its own kind, retaining some of the characters of their progenitors, and assuming others foreign to them all; and it will depend on their relative success in the struggle for life in a wild state, and upon the wants of man in a cultivated one, which of these shall be preserved, and for how long. Granting, then, that all are sprung from one, how does it happen that they are now so sundered geographically?

The discovery of the moraines of the Lebanon requires us to extend the influence of the glacial period into a lower western latitude than it has been heretofore proved to have reached. When perpe tual snows covered the great axis of the Lebanon, and fed glaciers which rolled 4000 feet down its valleys, depositing the moraines to which the Cedars in the Kedisha valley are now confined, the climate of Syria must have been many degrees colder than now; the position of the Cedars fully 4000 feet lower, and the atmosphere greatly more humid. Arguing from analogy, it is reasonable to infer that, at such a time, the Cedars formed as broad a belt on the Lebanon, as they now do on the Himalaya and in Algeria, and were continuous with those

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of the Taurus; and that these also descended proportionally lower and spread much further to the eastward. Again, in the Sikkim and Nepal Himalaya, I have found abundant evidence of glaciers having descended to fully 4000 feet below their present level; and this has been corroborated by numerous observers in the western parts of the same range; so that there, too, the Cedar forests may be supposed to have once descended several thousand feet, and to have extended westwards along the Persian mountains, till they united with the Taurus forests.

It is more difficult at first sight to connect the Algerian with the Asiatic forests; but here the recent discoveries of extensive modern changes in the form and extent of the Mediterranean basin come in aid. It is not now doubted that the remains of the African Hippopotamus and Rhinoceros in Sicily prove a former continental extension from the Tunis coast to that island, and the soundings between Cape Bon and Sicily appear to corroborate this view. It would be folly to assume it as certain, that the extension of these most recent discoveries will clear up the early history of the diffusion of the Cedars; but it is conceivable; and if proved, it is reasonable to suppose that their subsequent segregation in the four areas they now inhabit, was effected by the warmth of the period which succeeded the glacial epoch. During such a warm period the vegetation of the low levels would be driven to seek colder localities, and to migrate both northward and up the mountains, where it has left traces in the grove on Lebanon, and in a few arctic plants which I obtained on the very isolated summit of that mountain. Lastly, it is an established fact, that all plants of wide diffusion vary much, and that the extreme forms occur towards the limits of the area they occupy; whence, in the case of the Cedars, what may once have been three prevalent varieties in different parts of a continuous forest, became, by isolation and extinction of intermediate forms in intermediate localities, three permanently distinct races or sub-species, which we now recognize as Lebanon, Algerian, and Deodar Cedars.

EXPLANATION OF THE PLATES.

PLATE 1.-Cones and leaves of C. Libani, from the Lebanon. Figs. 1-4, Scales of various forms from one cone, ripened at Kew; 5, Seeds from the same; 6—7, Anthers (magnified); 8, longest, shortest, and mean sizes of leaves, from native specimens.

PLATE 2.-Cones and leaves of C. Atlantica, from native specimens. Figs. 1-4, Scales; and 5, 5, Seeds from the same; 6, Anthers (magnified); 7, longest, shortest, and mean sizes of leaves, from native specimens; 8, Leaf, from young cultivated specimen at Kew.

PLATE 3.-Cones and leaves of C. Deodara, from native specimens. Figs. 1—3, Scales; 4-5, Seeds; 6, Anthers (magnified); 7, longest, shortest, and mean sizes of leaves.

IV. ON THE MORPHOLOGY OF THE FEMALE FLOWER OF THE ABIETINEE. (De Abietinearum Carr. floris feminei structura morphologica. 4to. pp. 12. Regiomonti Pr.) By Professor Robert Caspary.*

THE structure of the female flower, or inflorescence, of Gymnosperms, has been the cause of more discussion than most questions of morphological botany. In earlier times, the views of botanists on this difficult subject were necessarily uncertain and arbitrary, because no accurate observations had then been made either of the perfect flower or of its evolution. As the study of morphology depends upon the correct knowledge of the taxis of the leaves and branches, the structure of the flowers of Gymnosperms could not possibly be understood at an earlier period. It is not my intention here to enter into details (which may be readily found elsewhere) regarding the various explanations which have been proposed; but I think it desirable to state the plain truth as respects the group of Abietineæ, so as to correct previous errors, and to obtain a basis of comparison to which the flowers of other Gymnosperms may be referred.

The true structure of the flowers of Abietineæ was described by A. Braun, as early as 1853, in the following terms, in a note of great importance, though short and modest, which has been entirely neglected by subsequent writers. "The seed-bearing fruit-scales of the cones of Åbietine, which lie in the axils of the bract-scales, have all the appearance of one-leaved shoots, but the progressive modifications of form exhibited by these scales in abnormally developed cones of Pinus Larix, prove that each scale consists of two leaves united together." In 1860 he expresses himself in a similar manner, only in more general terms, as to the structure of other Conifers and Cycads. The woody scales of the strobili of Abietineæ consist, according to A. Braun, of two carpels, which originate together, and are the first leaves of an undeveloped bud in the axil of the floral leaf.

Before these views of Braun were known to me I was led to the same conclusions, at Bonn, in the autumn of 1858, by the examination of larch cones, which had grown out into leafy branches in the axils of the scale. My observations on these were to the following effect:

Along the axis of these cones or strobili are inserted linear, elongated bracts, with the woody scales in their axils. The axis does not end with the uppermost scales, but is abnormally prolonged for several inches beyond the apex of the cone. Such strobili have been figured by Richard. The slender prolongation of the axis differs in

• Communicated by Dr. T. Thomson, F.R.S. An abstract of Dr. Baillon's views, referred to in this paper, is given in the Nat. Hist. Review, Vol. I. Bibliography, p. 92.

Individuum der Pflanze, p. 65.

Ueber polyembryonie und Keimung von Cœlebogyne, p. 243.

Mémoires sur les Conifères et les Cycadées, 1826, t. 13, f. 9, fig. repetita in

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