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specimens of Amygdalus davidiana. The few twigs of herbarium 
material that Mr. Woelkov showed me afterwards seemed to 
show, however, a difference between the two, as flowers and 
small leaves were developed simultaneously, while A. david- 
iana developes leaves after the flowers have passed. We must 
wait a little while, however, before accepting this creation 
as a genuine hybrid. 
"Looking over the ornamental trees I was struck with 
the fact that North America has more to offer to Russia in 
the line of hardy trees than Rusia to us. Some North American 
trees have become a feature of Russian parks and streets, 
like Robinia pseud-acacia, Praxinus americana* but especially 
the box-elder, Acer negundo, which is one of the hardiest 
trees here in Russia and is seen in almost all parks in com- 
pany with lilacs and Caragana arborescens. 
"I noticed, however, at Mr. Woeikov's place, some 
specimens of Ulmus turkestanica, which came originally from 
Djarkent, at the Chinese Turkestan border, and which trees 
are apparently very drouth and cold resistant. Salix alba, 
in varieties, is of promise as an ornamental tree on slightly 
moist places in the upper Mississippi valley regions. Alnus 
glutinosa, well fit to border water courses in cold regions, 
loves a sandy soil. 
"Populus trista from Kamchatka, a medium sized tree; 
very cold resistant. Populus wobsti with very large leaves, 
coming from Central Russia. Populus nigra, P. alba and 
P. tremula are hybridizing among one another at Mr. Woeikov's 
place, and the variation seen among the seedlings is most 
interesting. Some new types will evolve and we may expect,' 
perhaps, forms of dense-growing habit, of which the so- 
called Berlin poplar(P. laurifolia x P. suaveolens) is an 
example. 
"In shrubs I saw very little that is new. Hippophae 
rhamnoides exists in a few distinct varieties, of which the 
ones from central Asia are the hardiest and quickest growing. 
Mr. Woeikov states that plants from elevated Central Asia 
seem to be especially hardy in Southern Russia, such plants 
having been used to long periods of dryness and heat and not 
coming quickly into leaf, after a few hot days in spring; 
plants from Manchuria, however, though perfectly hardy in the 
wood, suffered severely from the heavy night frosts in late 
spring and many things from the Eastern United States were 
hurt on the same account. These observations I consider of 
immense value to us, as it gives us a clue where to obtain 
our material for the western sections of the United States. 
The great pity is, that elevated Central Asia is so poor in 
promising plants. Still there are the mountains of Northern 
Kansu, which Mr. Woeikov considers an unexplored mine of 
new shrubs and trees. He stated there are the following 
