132 THE FLYING SQUIRREL. 
to distinguish the sex by the marking on the wings, so I dissected 
them and the result proved them males. 
Again, I found a larva new to me, feeding on the soft maple. 
I obtained thirty-three good specimens. I was very anxious to 
rear these, so'I watched them closely, and plied them with fresh 
good food; if one fell or wandered from its food I replaced it, 
and continued this treatment until they would eat no longer. 
They went into the earth to undergo transformation, and in ten or 
twelve days thereafter, the rare, beautiful moth, Dryocampa rubi- 
cunda, made its appearance. Of these there were twenty-nine 
females and two males. The remaining two ‘either escaped or 
died in the earth. 
About the time these moths came out, another lot of the same 
Dryocampa caterpillars was brought to me, but these were pur- 
posely neglected. I found them more than once wandering about 
the box in quest of food ; some of these were killed by a parasite, 
others died from lack of food, so that the result proved only seven 
males, and no female. 
THE FLYING SQUIRREL. 
BY PROF. G. H. PERKINS. 
R dbaecnk 
_ Over a year ago, I bought of some boys in central Illinois 
a pair of flying squirrels (Pteromys volucella Des.). They were 
only a few weeks old but were already quite tame; indeed they 
had never been otherwise for they were taken before they could 
ee run from the nest and so were taught to be tame at the outset. 
Their habits have been very closely watched since I have had 
them in my possession, for so amusing and interesting are they 
that it is quite difficult to be in the room where they are without 
watching their movements. I have noticed some facts in regard 
to them which I do not find mentioned in any account that I 
have seen. Intense activity characterizes them at all times, but 
it is more intense at some times than at others. In warm weather 
. their movements are generally quicker and their exercise con- 
tinued much longer than in cold. In summer they are more noc- 
: turnal i in their habits than at other seasons. 
