60 THE OTTAWA NATURALIST. | May 
to all studunts who have watched the young caterpillar from the 
time it left the egg to that period. For such, few human experi- 
ences can equal the delightful suspense of watching for the 
bursting forth of the perfect insect from its frail chrysalis prison, 
through the walls of which the colors of the butterfly have been 
plainly visible tor several hours. 
The exercise suggested is simply to procure eggs of the 
Clouded Sulphur Butterfly and watch the development of the 
caterpillars through all stages to the perfect insect. To do this 
all the apparatus necessary is two or three 6-inch flower pots, a 
yard or two of mosquito netting, a few feet of wire and some 
india rubber bands. 
The first thing to do is to transplant into the flower pots 
good strong plants of Alsike or of common white clover. Any 
clover will do but these kinds are convenient to handle on account 
of their smaller growth. This should be done early in May and 
the plants will be well established bv the middle of the month, 
when the first specimens of the Clouded Sulphur Butterfly may be 
seen flying hurriedly along roadsides and over meadows. On 
catching a few of these it will be at once noticed that there are — 
among them two patterns of ornamentation on the wings. These 
indicate the sexes. The males (Fig. 1) have a regular black 
margin to all the wings, while the females (Fig. 2) have the mar- 
gin of the upper wings much wider with some yellow spots inclosed. 
Having caught two or three females put them inside a cage 
made over the potted clover plants by first bending two pieces of 
wire 18 inches long into hoops, and having crossed them at right 
angles over the plants, push the ends down into the earth. Over 
this framework stretch a piece of mosquito netting and keep it in 
place by putting an elastic band arouud the rim of the flower pot. 
The cage is now ready and by raising one edge of the netting the 
butterflies can be slipped into it, care being taken not to injure 
them in any way. The cage must then be placed in some shady 
place out of doors. In a couple of days, if the females are ready 
to lay, the exquisitively beautiful pale yellow, striated, spindle- 
shaped eggs will be seen standing erect on the upper surface cf 
the leaves. From this time on the notebook must be kept close 
at hand, and changes worth recording will occur every day. The 
