115 
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_ 
f of which had eaten canker-worms), Diptera and Coleoptera in 
e and four respectively, and Hemiptera in seven. Earth-worms 
( *e found in five, myriapods (Geophilus) in but one, and Arachmda 
tes and spiders) in nine. Grass-like plants were taken by thirty- 
and fungi by twenty-nine. 
Scanning the totals for each genus, a few results are noted which 
; worthy of special remark. First, we observe that at least two 
y abundant genera, represented by specimens enough to give us 
air probability that their average food is correctly exhibited, can 
•dly be classed as carnivorous insects at all, namely, Harpalus, 
h its nineteen specimens and twelve per cent, of animal food, 
l Anisodactylus, with its thirty-one specimens and twenty-one 
I cent, of the same. Amara and Amphasia should probably be 
ced in the same category, six specimens of the first and five of 
second having taken but twenty-three per cent, and seven per 
t., respectively, of food of animal origin. The excessively abundant 
modems ranks but little higher as a carnivorous insect, fifteen 
mples having derived only about one-third of their food from 
mal sources. On the other hand, twenty-three specimens of 
| genius and seventeen of Galerita had taken about nine-tenths of 
||iir food from insects, mites, myriapods and earth-worms. Thir- 
1 q specimens of Pterostichus had obtained three-fourths of theirs 
I! n similar sources, while Evarthrus and Calathus, represented by 
j en and six specimens respectively, had averaged ninety-tlnee per 
t. and sixty-seven per cent. 
Che fact has already been alluded to that the Carabidge proper 
1 eaten only animal food, and that nearly all this was of a fluid 
macter. 
lecond, we find the Carabidge dividing into at least three tolerably 
binct groups as respects their food : first, those which seem usually 
J seize their prey and suck its juices, and take vegetation rarely, 
it all; second, those which take a much larger ratio of animal 
d than of vegetable, but masticate and swallow it, as a rule, in- 
ding indigestible fragments; and third, those whose habit is 
entially vegetarian, but which still take solid animal food in 
finished ratios. A fourth group, consisting of Lebia and its allies, 
perhaps obscurely indicated by the facts relating to the three 
cimens of Loxopeza atriventris studied. This will probably be 
nd to feed largely upon pollen and fungus spores, after the man- 
j of the Coceinelfidge; and the fossorial Carabidge will, perhaps, 
j stitute a fifth. 
f we look now to the structures of these beetles for some expla- 
ion of their differences of habit, we shall find corresponding 
iations in the form and structure of the mandibles. Where the 
Indibies are long and curved, and are destitute of basal molar 
' cesses, but are provided at or near the middle of the cutting 
I e with processes relatively long and sharp, the beetle seems to 
1 substantially upon soft or liquid animal food. If they are of 
lium length, somewhat slender, broad at base and tapering dis- 
y, with the tip acute, and provided with basal processes which 
not especially prominent or sharp, the food is chiefly animal, 
solid structures are masticated and swallowed, and some vegeta- 
L 
