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Show 6LO ADD"EN"DA. be added to this list of animals as indigenous to America;" and it i~ evident from a prevw. us passe:a::(>T e , that the bones have been found fosstl. k'M dr . Ro(Ters states, that the remains of two kinds of elephant and t~Jrec m. s of ~xen have been discovered there ; as have, on two o~caswns, pal ts of the M e<Tat l1 er·m m. At Bi(T:::> Bone Lick' where the remams of the ele- hant, mas~odon, and ox, are so extraordinarily numerous, the mega 1o nyx ~ been found. and this is a parallel case to the contemporaneous emb:~ ment, in tl~e southern hemisphere, of the mastodon, horse, mega- 1 · nd tl1tlenum, a e other Edentata. The more I reflect on the. geo· - (Traphical distribution in the Old and New World of the~e gtga~tic 10 mammu·ce rs, d un·n (T the period antecedent to the present, m relatiOn 0 • t the existing faunas of North and South Amenca, now so strongly con-t~ asted with each other, the more pregnant with interest the case appears to be. I know of no other instance, in which :'e c.an thus almost m~rk the period of the splitting up of one great regwn mto .two well chaiac- ten.z e d zoo 1o gi· cal provinces · With respect to the a.n cient ra.n ge of t.h e genus E quns, I may add to wh•a t has already been sai.d , that ·1 ts 1re mams have been found from England in the west, to the Htmalaya m t 1e east, (Buckland's Reliquice Di!uvianm, P: 222,) and f~om. the western .coast ~f North America, to the eastern plams of Amenca m the southelD h~mi-h W may therefore suspect that a very little research would dJsco-sp ere. e , ' . · 1 k ver the remains of the horse, embedded in the frozen s01l of 1\amtsc 1at a, with those of the fossil ox and elephant ; and thus render comple~e the evidence, that we there see the ancient, but perhaps temporary line. of junction, since interrupted, between the fauna of what we call tl~e New world with that of the Old. But I doubt not, that the snow-clad heights of Chimborazo, Illimani and Aconcagua have seen as m~ny, and as.stra~ge forms of animals, pass by and become extinct, as ever did the Alp me pmnacles, or those loftiest ones of the Himalaya. Page 2(}8. When contrasting the productions of the eastern coast of South America with those of the western, and likewise with those of the corresponding ~arallels of latitude in Emope, I should have added (line 15). after the grape and fig, as flourishing in lat. 41°, the peach, and the nectarme (both of course standards), water and musk melons, batatas dulces (Convolvulus batatas), the olive and the orange; the latter, however, had only been lately introduced, but it promised to succeed well. Page 272. I have spoken of the low latitudes in which tropical forms of vegetation ADDENDA. 611 are found in the southern hemisphere, and likewise of some mammalia and of birds. With respect to the parrot of the Strait of Magellan, Macquarrie Island in lat. 55° S. and long 160° E. offers an analogous instance, in possessing a species of this genus. I am, however, now enabled to bring forward a more important observation, as directly bearing on the evidence by which geologists have chiefly judged of the climate of ancient Europe, namely, on the character of the marine productions of the southern hemisphere. In my journal I have remarked that the southern seas teem with life, under innumerable forms ; and the truth of this remark is amply attested by the vast herds of great unwieldy seals with which the shores of Patagonia, the Falkland and the Antarctic islands, were, according to the nanatives of all the early navigators, almost covered. Having mentioned these facts to Mr. George B. Sowerby, he informs me, that the shells of the southern part of the southern hemisphere have some affinity in general character with those of the intertropical seas, or rather that they ar~ of much larger size and of more vigorous growth than the analogous species (excepting the chitons of California) under corresponding zones in the northern hemisphere. Thus the immense size of the Patellre, Fissmellre, Chi tons, and Barnacles of the Strait of Magellan, and the large size of the former at the Cape of Good Hope, may be taken as instances. On the east coast of South America (in lat. 39°) three species of Oliva (one of large size), a Voluta (and perhaps a second species), and a Terebra, are amongst the most abundant shells on the mud-banks of Bahia Blanca. Another species of Voluta is found as far south as 45o, and there is some reason to believe, even much furthei·. Oliva, Voluta, and Terebra are amongst the best-characterized tropical forms, that is, both the individuals and species of these genem are extremely abundant in the intertropical seas, whilst they are very rare, or do not exist, on the shores of temperate countries. It is doubtful even if one small spe.:ies of these three genera, an Oliva, inhabits the southern shores of Europe ; whilst in a lligller· latitude, on the coast of South America, species of all three are the most abundant kinds. At Bahia Blanca many of these shells are embedded in gravel, and have been raised above the level of the sea. Now let us suppose that the climate of South America and of the surrounding seas were to undergo some chang~, so as to become in every respect like that of Europe; it can, I think, scarcely be doubted, that the shells of the abovementioned genera would gradually become extinct, and be replaced by others better adapted to the new climate. What, then, would a geologist say, who entertained the generally-received opinions on the distribution of organic beings in accordance with our knowledge of the northern hemisphere (or, rather, in this imaginary case of both hemispheres), when be found these gravel beds abounding with Olivas, Volutas, and Terebras ?-such 2 Q 2 ·* |