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 blending; 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 perpetual 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
