| OCR Text |
Show 1878.] HEMIPTERA OF ST. HELENA. 447 African one, and characteristic of Southern extra-tropical Africa. The genera Phylica, Pelargonium, Mesembryanthemum, Osteosper-mum, and Wahlenbergia are eminently characteristic of Southern extra-tropical Africa; and I find amongst the others scarcely any indication of an American parentage, except a plant referred to Phy-salis1. The Ferns tell the same tale: of 26 species, 10 are absolutely peculiar ; all the rest are African, though some are also Indian and "American. The botany of St. Helena is thus most interesting; it resembles none other in the peculiarity of its indigenous vegetation, in the great rarity of the plants of other countries, or in the number of species that have actually disappeared within the memory of living man . . . . Probably 100 St.-Helena plants have thus disappeared from the Systema Naturae since the first introduction of goats on the island. Every one of these was a link in the chain of created beings, which contained within itself evidence of the affinities of other species, both living and extinct, but which evidence is now irrecoverably lost. If such be the fate of organisms that lived in our day, what folly it is to found theories on the assumed perfection of a geological record which has witnessed revolutions in the vegetation of the globe to which that of the flora of St. Helena is as nothing! " Mr. Melliss, whose interesting work on St. Helena I have had frequent occasion to refer to, says2:-"Other theories may be appealed to in order to account for the presence and position of this wonderfully curious little flora. Continental land at one time spreading over the South Atlantic Ocean, with its own peculiar flora and fauna, has been started as a plausible theory; but the geological investigation of St. Helena forbids us to look upon it as a remaining portion of some disappearing continent to which the last vestige of a flora, still struggling for existence, may be clinging; and the great depth of ocean3 around it also seems to deny the possibility of its connexion at any time with either African or American land. Still we cannot tell what geological changes, hundreds or even thousands of centuries may have witnessed in that portion of the globe, leaving, perhaps, this unique little floral remnant, now fast disappearing, as almost the only record of what once was. So far, therefore, the manner in which this once incandescent mass first received its flora, whether by the agency of birds or atmospheric and oceanic currents, or direct from that Hand by which all things were created, still remains un-fathomed." Of the class Arachnida, Mr. Melliss ** states:-" Mr. Cambridge says, in reference to the character of this portion of the island fauna, after his final examination of the several collections, that ' the European stamp observed upon in regard to the spiders of the former collection is thus equally marked in those now recorded and described.' It is worthy of note that the native Spiders are, almost as a rule, least 1 Subsequently referred to a new genus, Mellissia, Hk. f. 2 P. 225. 3 "St. Helena is said to be separated from the continents of Africa and America by a depth nowhere less than 12,000 feet." * L. c. p. 206. |
