CREVICHON. 
F it were possible, without too great danger and inconvenience, 
to get at all the islets in the Channel Islands which are covered 
with verdure, it would be an interesting study to compare their 
vegetation one with another, having regard to area, elevation. ex- 
posure, and so on. It is possible that these green islets would be 
found to differ more widely than might at first sight be supposed. 
But it is practically impossible to land on many of them, because 
either the base is a vertical wall of smooth rock, or else the current 
is too strong to permit the approach of a boat, except on rare 
occasions. 
Much may be learnt, however, from those semi-detached frag- 
ments which have been severed from their mother-islands within 
geologically recent times, but are still connected with them at 
extreme low tide. The finest example within the area dealt with in 
this book is Lihou, on the west coast of Guernsey, of which an 
account has already been given. On the opposite side of Guernsey, 
off the Vale coast, there are three small islets, accessible at low 
water: the northernmost of these, called Houmet Homptolle, is 
about eighty yards long by sixty wide, the area above high-water 
mark being roughly about an acre: the surface is fairly even, and is 
covered with grass and low plants. A careful examination of this 
islet some years ago shows that the vegetation consists of fifteen phane- 
rogams, one of which, Lepturus filiformis, I certainly never expected 
to find in sucha locality. It may be interesting to give here a list of 
the Homptolle plants for the purpose of comparison: Cochlearia 
danica, Lepigonum rupestre, Silene maritima, Trifolium repens, 
Lotus corniculatus, Daucus gummifer, Thrincia hirta, Sonchus 
oleraceus, Armeria maritima, Plantago Coronopus, Beta maritima, 
Agrostis alba, Sclerochloa loliacea, Festuca ovina, Lepturus filiformis. 
Intermediate in size between Lihou and Homptolle, but differing 
in character from both, is the pyramidal rock called Crevichon, 
which lies off the north-western end of Jethou. It is a little more 
than three acres in extent, and from certain points of view makes an 
extremely pretty picture. There is an old quarry on one side, from 
which a large quantity of granite was taken many years ago, but the 
carting away of the stone must have been an achievement of some 
difficulty. This little islet is of additional interest to a botanist from 
the circumstance that it.was visited by Professor C. C. Babington 
