154 MOTHS AND BUTTERFLIES. 
quite near them and watch them guide their long flexible tongues into 
the tiny flowers. The motion of their wings is so rapid that they 
make a slight whirring noise and in the half-light are almost invis- 
ible. The larva is green with light oblique stripes on the sides, and 
it feeds on the leaves of the apple though it is rarely sufficiently 
plentiful to do much damage. 
Sphinx chersis. 
On the ash and lilac, in September, may be found a plump, hand- 
some green caterpillar, whitish on the back and having seven oblique 
light yellow stripes on its sides edged above with dark green. ‘This 
is the larva of Sphing chersis. The moth is ashen gray in color with 
several black and white bands on the sides of its body, two heavy 
black lines on its lower wings and a few pen-like markings in black 
on its forward wings. It is a large powerful moth and has a strong, 
rapid flight. 
Sphinx drupiferarum is also a good-sized moth, being four inches 
or over in expanse of wing. The general color is dark sooty brown. 
The outer margin of all four wings is light brown while a large area 
along the upper margin of the upper wings and a band across the 
lower wings is gray. Black and white bands alternate on the sides 
of the body. The larva feeds on the leaves of the plum and hack- 
berry. It is light green with white stripes edged above with purple. 
