370 
where no earthquake has ever been recorded; for, though there 
seems to be sufficient evidence that Grand Cayman is being steadily, 
and from a geological point of view rapidly, lifted up, this eleva- 
tion can hardly be rapid enough to have much effect on the 
establishment of new plants. 
early seventies of the last century as an ordinary launching place 
for canoes is now two feet or so too high above the ordinary tide 
level for this to be done with any safety. Further evidence is 
swamps, which in a short time dissolves even such massive shells as 
those of Strombus} and planes down the underlying rock to a more 
or less flat surface showing excellent sections of its fossil shells ; 
harder lumps being left here and there as rugged “islands ”—to 
disappear more slowly.{ 
_ This elevation can perhaps be satisfactorily accounted for by the 
inward and ultimately upward thrust of the ever growing wall of 
coral debris on the seaward face of tle reef. Seeing then that it 
may only be four or five times in a century that seeds are likely to 
be left sufficiently out of the reach of ordinary high tides to be able 
to do much more than start their growth before they again find 
themselves in salt water, and that even so they must in most cases 
be able to grow in a soil which is toa large extent composed of 
calcareous sand, it is small wonder that the immense number of seeds 
thrown ashore alive should produce comparatively few seedlings. 
And as soon as a seedling begins to show itself it is exposed to 
attack by land crabs. 
Two species are particularly destructive in Grand Cayman, 
Cardisoma guanhumi and Gecarcinus ruricola(?). The first, being the 
* Much of this rock is hard enough to make sparks from steel. 
ew weeks. 
; t n this connection to compare the account given of the 
ptr on Little Coco in Natural History Notes from H.MI.M. Subvey Steamer 
7 —— No. 25. The vegetation of the Coco Group. By D. Prain in the 
ourn. Asiatie Soc. Bengal LX, Pt. II. No. 4, 1891, pp. 288 et seq.—Ep, 
