A 
THE COTTON CATERPILLAR. 213 
stimulate us anew to prosecute with still greater ardor deep-sea 
dredgings off our coast, particularly the northeast extremity of 
the St. Georges Banks, with the hope of finding that now strangely 
interesting shell, Leda truncata, which has been brought home from 
the seas of Greenland in a recent state by arctic voyagers ; and on 
the other hand, to investigate the clay beds of the coast of New 
England, and Canada and Labrador with the hope of finding the 
Arca pectunculoides, which we can now with some degree of safety 
predict will be eventually found. The kind of bottom the writer 
found on the northeastern end of St. Georges Banks, and which 
_ proved so remarkably rich in molluscan and vermian life, was a 
sandy mud, much like that of the richest fossiliferous beds in our 
glacial formation. 
We have but glanced at the identical features of the glacial phe- 
nomena of the Alps, Scandinavia and northeastern America, a mat- 
ter which our geologists have doubtless each observed for them- 
selves, and which struck Prof. Agassiz when he first arrived in this 
country after his years of exploration in the Alps, and journeys in 
Scotland and Wales, but which will perhaps suffer repetition in a 
popular journal of this character. As Humboldt early in this cen- 
tury expressed his delight at finding identical rocks in the New and 
Old World, the student of the superficial deposits that cover these 
rocks cannot restrain his delight at finding them almost identical 
in both hemispheres. Indeed it may be a comfort to the American 
student of glacial phenomena to know if he is debarred from visit- 
_ ing the glaciers of the Alps or Norway, or even those of the Rocky 
Mountains, that in the northern states, their marks are as freshly 
preserved as in the Old World, except at the very edge of the 
glaciers themselves when photographs will supply the place of 
actual vision. 
THE COTTON CATERPILLAR. 
BY LEWIS A. DODGE. 
rn ee as 
Turre are two kinds of insects which feed upon and destroy the 
cotton crop. The boll worm (Fig. 39, caterpillar and moth) eats 
only the bolls or pods containing the unripe cotton lint. It confines 
