THE CANADIAN ENTOMOLOGIST. 43 
that we need not occupy our space with any special description. (Fig. 
; Fig. 11. 
II, with the comparatively few 
3 black spots, represents the male. 
=} Fig. 12, the female, with its much 
more numerous and conspicuous 
spots and markings.) 
The chrysalis (Fig. 13, 2) is over 
half an inch in length, of a light 
: bluish-gray color, more or less pro- 
fusely speckled with black, with the projecting portions tinted with pale 
yellow or flesh color, and marked with large black dots. The caterpillar 
(Fig. 13, @) varies in colour from ARE 
‘deep to pale bluish and green; it 
has four longitudinal yellow stripes, 
and is thickly covered with black © 
dois As inj) the other species 
there are two broods in the year, 
and the winter is passed in the pupa 
state. In the Southern States it is 7 A 
a very injurious insect, but here it a aie Thee 
Fig. 13. 
is too rare to be more than 
an interesting curiosity. 
Another species of Pieris 
(P. frigida, Scudder) has 
been taken in Labrador and 
on the Island of Anticosti, 
but it is not likely ever to 
spread much, or to be ranked 
amongst ‘ common insects.’ 
ON THE GEOGRAPHICAL DISTRIBUTION OF SOME GENERA 
OF CANADIAN INSECTS. 
BY FRANCIS WALKER, LONDON, ENGLAND. 
Isosoma.—So much has been lately written about this genus that it 
may be dismissed with a few words. The Æwryfomidae, to which it 
belongs, were considered by Nees to be in a debatable state between the 
