a2) Peo 
observations. His classification of the sand-deserts will be 
referred to later. 
The Petersburg Forestry Journal (1901) contains an im- 
portant article by W. PaLezky on “Sand-binding on the Mid- 
Asiatic Railroad”, and a later contribution has appeared in the 
Russian Forestry Journal (1908 nos. 31 and 32). The author 
has for many years superintended the operations for the 
protection of the Transcaspian railroad against sand-drift, — 
and in 1899 I had the pleasure of visiting parts of this un- 
dertaking under his able guidance. 
The paper begins with description of the features of the 
different landscapes and the dune-formations, the dangers 
arising from sand, and the different ways in which the drift 
may block the railroad. 
The most effective means of settling the sand-drift is to 
encourage vegetation; artificial means such as the planting of 
green turf and reeds are also resorted to. Trees are planted 
extensively along the railroad in belts 425 to 530 metres wide. 
Later on these spread naturally and have in some places 
reached a width of 2—3 kilometres. 
The natural conditions of the sand-deserts are extra- 
ordinary, he says. It does not rain from May till November, 
and the precipitation during winter and spring is insignificant. 
Ground-water containing bitter-salt, moving sands and the 
broiling heat of summer are other impediments to a luxuriant 
vegetation. In combating the sand it is therefore necessary 
to select local plants acclimatised to the conditions, and 
sufficiently aggressive to establish themselves. Experiments 
with introduced plants are, however, also made. The prin- 
cipal species used for planting are: Saxaul (Haloxylon Am- 
modendron), Salsola Arbuscula, Ammodendron Conollyi, Ere- 
mosparton aphyllum, Salsola subaphylla, Smirnowia turkestana, 
Astragalus paucijugus and A. Ammodendron, Aristida pennata, 
Carex physodes and various species of Calligonum. Short 
notes on their properties are given which we shall refer to 
later on. 
Nurseries have been established in which stocks are raised 
for transplanting. As the desert plants often have very long 
roots which would be damaged by transplanting, the nursery 
