75 
tinct species, which he calls Populuspyratnidalis, It is believed by 
the best authorities to have originated in Persia ; some writers, on 
the other hand, state that it is truly indigenous to Italy, but the evi- 
dence, however, we think is strongest in favor of Persia, from 
whence most probably it was introduced into Italy, where it is now 
a favorite tree and extensively grown. Lord Rockford has the 
credit of having imported this Poplar into England, by means of 
cuttings brought from Turin in the year 1758. The original trees 
raised from those cuttings are supposed to have been planted at 
Blenheim, in Oxfordshire. — Garden. 
Trees of the United States. — There has recently been placed on 
exhibition, at the New York Museum of Natural History, an almost 
complete representation of the trees of the United States, between 400 
and 500 trunk sections of the different species. These specimens 
are about five feet eight inches long each, cut in such manner as to 
display their barks and the transverse and longitudinal sections of 
the wood. This is done by cutting away one side of each specimen 
at the top to the depth of one-half the diameter of the trunk and for 
one-third of its length. One-half of each exposed portion is pol- 
ished to illustrate the effect of this treatment of the wood, the re- 
mainder being left in the natural condition, with the top of the upper 
divided part finished by beveling. In the case of trees of commer- 
cial importance this form of representation is supplemented by care- 
fully selected planks, or by burls, showing better than the logs the 
true industrial value of the wood. Among specimens of this kind is 
a plank of redwood {Sequoia sempervirens), measuring 8^ feet in width. 
A species remarkable for slow growth, and which is only 24 inches 
in diameter, shows an age of 410 years, being, the oldest tree in the 
collection. This is Picea Engelmanni, named for its discoverer, 
Dr. Engelmann, and known also as Engelmann's spruce. Another 
example of slow growth is seen in Finns edulis,^ or edible pine, from 
Arizona, called also nut-pine. The seed of this pine, which resem- 
bles a good-sized bean, is used by the Indians for food. A tree of 
this species which is 300 years old measures only 15 inches in diam- 
eter. Another specimen, which is 2>^} y^^^s old, shows a diameter 
of 37 inches. It is the western shetl-bark hickory {Carya sulcata), 
from Allenton, Mo. The same locality is represented by a specimen 
of Tilia Americana, or basswood, which is 40 inches in diameter, 
and 150 years old. 
This valuable collection, numerically exceeding that made \n 
connection with the census reports, includes examples of many curi- 
ous and interesting species, of which probably the complete natural 
series could never have been viewed in their native soil by any sin- 
gle traveller, however diligent. 
Among the extraordinary specimens is a representative of Texas. 
This is the Cereus giganteus, which resembles a fluted column. It is 
a plant which can be readily taken all to pieces. Its component parts 
are in the form of vertical sections of twisting curvatures in the hne 
of their circumference, whereby one portion is fitted exactly to 
another. They can be* separated without the slightest difficulty, in 
the absence of any heart at the centre for their attachment. , The 
