16 THE OAK-VEGETATION OF AMERICA. 
most beautiful scarlet velvet, on account of the dense felt which covers 
them; as they advance in growth, the red colour changes into pale 
yellow or whitish, the felt on the surface is rubbed off, and a dull 
green colour succeeds; they become very thick, almost cartilaginous, 
fragile, with the margin recurved, so as to resemble the hollow of 
a hand or spoon, whence the natives call the tree the Spoon Oak 
(encina de cuchara). Q. dysophylla, spicata, aud callosa have similarly 
thick leaves. 
In the eastern valleys of Oajaca, the Oak descends to an elevation of 
a few thousand feet only. The relative condition is here nearly as in 
the eastern slope of the Cordilleras. Among the Oak-forms here, we may 
name the remarkable Q. Skinneri, first known from the western coast 
of Guatemala, having a nut of 5$ inches in circumference; further Q. 
salicifolia and tomentosa. In the valley along the Rio de las Vueltas, 
I have again met with Q. petiolaris, found also on the eastern slope of 
the Cordilleras at an elevation of 2500 feet. The Oaks which ascend 
. highest on the Oajaca Cordilleras (Sempoaltepec, Pelado, Cumbre de 
.. Ocote, and Tauga) are found at an elevation of 10,000 to 11,000 feet, 
in the form of crippled shrubs, only a couple of feet high. 
The western Cordilleras have Oak-forests like the eastern, but they 
are little known, because their investigation by travellers is attended 
with great difficulties; the mountains being exceedingly scantily in- 
habited ; and a protracted sojourn in those high regions where the Oak 
is found, being within reach only of the wealthy naturalist. My jour- 
ney across the western Cordilleras towards the southern happening at 
. a season, when the acorns were very little developed, the determination 
_ of species became impossible; my data concerning these are therefore 
scanty. The Oak-forests of that part are far from being so fine as 
those of the eastern Cordilleras, resulting from the dryness of the cli- 
mate; I may name among the species Q. nitida, acutifolia, glaucescens, 
and callosa. 
à The nature of the vegetation of Guatemala is as yet extremely im- 
perfectly known. There exists no connected account of it whatever. It 
is not to botanists that we stand indebted for the species from thence, 
but to collectors in other walks of life, who have gathered specimens 
of growing plants about their places of residence, and transmitted 
_ them to Europe. We owe to the English merchant Skinner, the 
English collector Seemann, and the known German collector -Hartweg, 
