304 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 
is able to give the results of his own extensive experiments in 
the cultivation of many of those exotic trees. 
In the second section is included a most valuable table 
dealing with the forest zones, which exhibit similar climatic 
conditions in North America, Europe, and Asia. ‘Altogether, 
the author distinguishes six principal zones based on similarity 
of climate and forest Flora, viz.:— 
(A) Tropical Forest Zone — The Palmetum. 
(B) Sub-Tropical Forest Zone of the Evergreen Oak and 
Laurel Tree—The Lauretum. 
(Ca) Temperate Warm Zone of the Deciduous Forest, 
Warmer half—The Castanetum. 
(Cb) Temperate Warm Zone of the Deciduous Forest, 
Cooler half—The Fagetum. 
(D) Temperate Cool Region of the Spruce, Silver Fir, 
and Larch—The Picetum or the Abietum or the 
Laricetum. 
(Z) Cold Region of the Scrubwood or Dwarf Trees, 
Forest Limit—The Alpinetum or Polaretum. 
All of the above zones, except A, are represented in Europe. 
We strongly recommend a careful study of this and the other 
sections by all those who are interested in the cultivation of 
trees—indigenous or exotic—for profit or ornament. There is 
no other source from which so much important and valuable 
information can be obtained. 
The third section consists of a most lucid and_ intensely 
interesting dissertation concerning the capability of exotic trees 
for cultivation in Europe. This is treated under three headings, 
viz., Acclimatisation, Naturalisation, and the Locality from which 
the seed comes. These are questions which, naturally, are 
of the greatest interest to British foresters. It will be readily 
admitted on all hands that opinions regarding these various 
problems are not at all uniform, and those who are interested 
in these matters could not. do better than turn to this work, 
where they will find the subject dealt with from its foundation. 
Space forbids our entering into detail, but there are other 
eight sections or chapters likewise replete with information and 
illustrations regarding exotic trees. Their distribution, nomen- 
clature, recognition, cultivation, and uses,—in fact everything, 
so far as is at present known about their botanical, sylvicultural 
and arboricultural characteristics, has been given by the author 
