226

Tenth Census
of the
United States.

[Rhuss typhina] was introduced into
the preliminary catalogue entirely on
your authority; but as both Engelmann
and Parry declare that they have never
seen this species west of the Mississippi
River I feel that there may possibly be
some error in regard to it somewhere.
Can you send me an authentic Iowa
specimen, that I may have something
to show for the statement?

I did not before know that the wood
of the Gleditschia could be used for the
hubs of wheels. Proper material for this
purpose is getting scarce in the United
States and I should like to know some-
thing more in regard to the extent