370 BAKER’S NORTH YORKSHIRE. 
Populus tremula IL. British type. Native. Area 
general. Range o-550. Frequent in woods and hedge-rows, 
ascending to Cronkley and Holwick Scars. Doubtless it is an 
inhabitant of the Yore district, but I have no note of its 
occurrence. 
Populus nigra L. English type. Denizen. Area general. 
Range 0-300. Frequent in hedge-rows and by stream-sides 
throughout the lower zone, but quite doubtful as an indigenous 
tree. Populus dilatata is not unfrequently planted in the low 
country. Populus monilifera occurs in plantations up to 350 
yards, and succeeds better than almost any other tree in ex- 
posed situations along our sea coast. 
Salix pentandra L. Scottish type. Native. Area 
general. Range 0-350. Frequent along stream-sides and in 
hedge-rows and damp woods throughout the lower zone, 
ascending to the lower part of Whitsundale. 
Salix fragilis L.* including S. decipiens Hoffm. and S. 
Russelliana Smith. Britishtype. Native. Area general. Range 
0-250. Common by stream-sides and damp woods in the lower 
zone, ascending to the fish-pond upon Lartington Moor. 
Salix alba L. British type. Native. Area general. 
Range o-200. Common in similar situations to the preceding, 
with which it is often associated. Both are commonly planted 
throughout the lower zone. Salix cerulea and Salix vitellina 
both occasionally occur. 
Salix triandra L. English type. Native. Area 9 87 
65.321. Range o-150. Frequent by stream-sides in the low 
country, and often planted in osier-grounds. Salix unduiata I 
have met with sparingly in an osier-ground in the neighbour- 
hood of Thirsk. 
* A large number of Willows from the neighbourhood of Richmond and from Wensley- 
dale were contributed by Mr. Ward to Leefe's ‘ Salictum Britannicum,’ A series of notes 
by Dr. Anderssen, the monographer of the Swedish Willows, respecting these specimens 
and others contained in the fasciculus are given in the Botanical Gazette, vol. 3, page 57- 
t 
