THE FORKED BUTTERFLY. 185 
Mr Say several times in the north-west territory, 
during the progress of the late expedition under the 
command of Major 8. H. Long, over that region. 
In the vieinity of Fort William, an establishment of 
the Hudson Bay Fur Company, it frequently oc- 
cured in the month of September, whilst the party 
remained at that place. It is closely allied to the 
_ Polychloras and Urtica of Europe, but is sufficiently 
distinet from either. 
The larvee of the genus Vanessa live on plants of 
little altitude, and are often gregarious ; they are 
armed with numerous, long, rigid, dentated spines, 
which, like the quills of the hedgehog, constitute 
their only defensive weapons. The chrysalids are 
attached to a fixed object by the tail, and in this 
reverse posture quietly wait the period of their final 
emancipation and perfection, 
