156 Mr Trevelyan on the Vegetation and Temperature 



Oats and rye have been tried, but seldom with success. Tur- 

 nips and potatoes thrive well. 



Frosts, which are not frequent, and seldom severe, are occa- 

 sionally of long duration. About the middle of December 

 1815, one commenced, which lasted till April 1816, and having 

 come when the ground was covered with snow some inches 

 deep, the surface of which had thawed, the freezing of this pre- 

 vented the sheep, one of the most important productions of the 

 islands, from obtaining their food, so that a very large number 

 of them perished, as many, it is said, as 30,000. In the island 

 of Stromoe, out of 16,517, there were lost 7870, or nearly one- 

 half.* 



In the coal and fossil wood occurring in it, and in the clay 

 which accompanies it, there is evidence, but probably in a very 

 different state of things, of the former existence of timber here ; 

 although it may, indeed, have been floated into this locality, 

 and subsequently elevated into its present situation, as appears 

 to have been the case in other parts of tlie globe.-f- 



In the peat-bogs occur the remains of birch trees, which do 

 not now grow in these islands, having probably been extirpated 

 by being used as fuel. 



The Flora of these islands contains (as far as hitherto ascer- 

 tained) 581; plants, viz. 



ACOTVLEDONES. 



P'ungi, 7 



Lichenes, . • . . 50 



Algae, 127 



Characese, .... 1 



Hepaticae, .... 22 



Musci, 85 



Filices, • 21 



313 



MONOCOTYLEDONES, ... 83 

 DiCOTYLEDONES, 187 



270 



583 



to a height of 200 feet, anc. in a northern, to 100 feet above the sea. See " For. 

 Historic og Statistik," 1822, p. 170. 



* Lyngbj'e, in a periodical entitled, " For Historic og Statistik," 1822, vol. i. 

 p. 133. 



+ This fossil wood appears to belong to the Conifera, as will be more particu- 

 larly explained in a future communication. 



