107 
:d,—from which it has resulted that we know their habits only in 
most conspicuous situations, and have not a fair idea of the 
serai average of their food. Neither have observations of any kind 
n numerous enough to enable us to detect clearly differences of 
d habit in different species or genera of these families; but, with 
ght occasional exceptions, all Carabidae have been classed together 
( essentially carnivorous. The following notes are a contribution 
a more exact knowledge of this subject: 
Clie method followed has been that of dissection. The alimentary 
lals of beetles, taken in a great variety of situations, at various 
-sons and at different times of day, have been removed, placed in 
cerine on microscope slides, and opened with small knives and 
unted needles, so as to display the contents completely. These 
ye been studied with whatever power of the microscope was neces- 
y, and mounted as microscope slides for permanent preservation 
1 repeated examination. 
y. few special collections of predaceous beetles were made in situ- 
Jjons where some particular species of noxious insect was particu- 
: ly abundant, with a view to determining to what extent the latter 
U preyed upon by its supposed enemies. 
i* 
Tiose from the orchard infested by canker worms, and those from 
orn field overrun by chinch bugs, were made by myself; the other 
ects dissected for this report, were partly obtained in the course 
miscellaneous collecting, and partly secured for me especially for 
purpose, by one of my entomological assistants, Mr. F. M. Web- 
L', who kept careful notes of the situations in which the specimens 
re taken, the hour of day when they were captured, and the objects 
>n which it seemed probable that they had lately fed. Examples 
the latter were frequently bottled, with the specimens, for com- 
•ison. 
The Predaceous Ground Beetles (Carabidce). 
Tiis large and important family of beetles is distinguished by their 
ider or filiform or slightly tapering antennae, taken in connection 
ill their five-jointed tarsi; by the articulated outer lobe of the 
if xillae, giving an appearance of six palpi, and by the large egg- 
'bped posterior trochanters. 
‘Tie fourth and fifth tarsal joints are not connate, but the first 
ee ventral segments are; and the first ventral segment is divided 
i three parts by the hind coxal cavities. The antennae are eleven- 
lted, and inserted at the sides of the head, between the base of 
mandibles and the eyes. 
ls their common name implies, they are found mostly on the 
mnd. They never attempt to escape by flight, but run with 
at rapidity. 
i ly notes upon the food of this family are derived from the dis- 
! tion and study of one hundred and twenty-five specimens, repre- 
if ting thirty-eight species and twenty genera. Eighty-two specimens 
■e collected in miscellaneous situations, twelve were taken in a 
1 infested by cabbage-worms, ten in a corn-field overrun by 
1 1 
