14 THE VOYAGE OF H.M.S. CHALLENGER. 



Concluding Remarks. 



From its composition it is evident that the present flora of the Bermudas is of com- 

 paratively recent derivation, though not so recent, perhaps, as might at first be supposed. 

 Whence it was derived, the foregoing tables and explanations sufficiently show. Briefly, it 

 is not of purely West Indian origin, but was derived from the West Indies and that region 

 of south-eastern North America where the West Indian and North American types 

 of vegetation overlap each other. Whether it was formerly richer in indigenous, and 

 possibly in endemic species, is problematical ; but the extreme rarity of many of the 

 indigenous species at the present time seems to indicate that such may have been the case, 

 though the probability remains of their being casual introductions unable to spread. That 

 the islands were ever clothed with a more ancient flora is unlikely from what has come to 

 light through excavations, dredging, and other operations. 



The peat or peaty mud of the marshes consists of the remains of ferns, sedges, and other 

 plants which still inhabit them. It is of great depth in places, and in it are sometimes 

 found trunks of the cedar of a larger size than any of those now growing in the islands. 

 In 1872 Sir J. H. Lefroy, then governor of the islands, caused some borings to be made 

 in Pembroke Marsh, the deepest of which was forty-six feet ; and these borings afforded 

 evidence that the peaty mud reached to the limestone bed of the marsh basin. From Mr 

 Oswald A. Reade we learn that a great deal of dredging has lately been done in Hospital 

 Bay ; and it is surprising, he says, what a number of trunks of cedar have been brought up, 

 and in such good preservation too, that it would seem the " greater Bermuda" had not been 

 so very long submerged. They were covered with a layer of peat, and over that foramini- 

 fera, &c. Under such conditions, of course, the trunks would be almost imperishable. 



The means for conveying seeds from the West Indies and Continental America to the 

 Bermudas are so obvious, that it seems almost superfluous to discuss them. From actual 

 observation it is known that seeds cast ashore by the waves have germinated and grown 

 into plants ; and the numerous birds that visit the islands can hardly fail to convey seeds 

 in their claws, feathers, or excrement. The seeds or seed-vessels of the majority of the 

 Bermudan plants may be classified in three or four categories — (1.) Large seeds, like many 

 of the Leguminosce and Ipomcea pes-caprce, that will bear immersion in sea-water for a 

 considerable period without losing their vitality ; (2.) small seeds or seed-vessels, such as 

 the Ciipcracece, some of the Composites, &c, that might be conveyed in small patches of 

 mud adhering to the claws of marsh birds ; (3.) seed-vessels having a fleshy envelope, 

 and containing hard seeds that pass through the alimentary canal of a bird without 

 injury : nearly all the woody plants in the island have seed-vessels or fruits of this kind ; 

 (4.) seed-vessels furnished with hooked appendages, by which they become attached to 

 other objects. There are few of the last kind in the Bermudan flora, Tn'umfetta being the 



