16 BUTTERFLIES. 
and a quarter long, varying in color from a light brown to 
a greenish-yellow; they are marked with fine black and yel- 
low lines. The numerous spines clothing the caterpillar are 
branched and differ in color, some being dark brown, others 
orange or yellow, the branches of the spines are frequently 
tipped with black. Notwithstanding the forbidding and 
threatening aspect of these caterpillars they can not inflict 
any injury to our hands. As soon as the full size has been 
reached, the caterpillars select some secluded spot in which 
to change to pupe orchrysaldis. They spin for this purpose 
upon a leaf or a twig a minute pad of silk. In this little 
carpet the hind leg of the caterpillar are fastened, after 
which it hangs suspended with the head downwards. In 
the course of two or three days, after contracting greatly in 
length, the old skin is shed, and an angular looking chrys- 
alis of a brown color appears, which is finely ornamented 
with silvery spots. Inabout ten days the butterfly appears 
in all its beauty. 
We have in Minnesota two annual generations of this 
insect; the first appears late in June and the second late in 
August and during September. 
The caterpillars of this insect feed also upon the hop, 
elm, nettle, false nettle and basswood, but prefer wild and 
cultivated gooseberries and currants. 
Other closely allied species of Grapta also feed occasion- 
ally upon the cultivated currants and gooseberries, but as 
their habits are almost identical with that of comma, it is 
not necessary to describe them. 
Remepies.—Hand-picking is in most cases all that is 
needed to keep this insect in check. In cases where we have 
to fight at the same time other injurious insects of the cur- 
rant and gooseberry, it would be best to use a little Lon- 
don-purple or Paris-green. Of course none of these poison- 
ous substances should be used at a time when the fruit is 
ripe or nearly ripe. 
