ECONOMIC EELATIONS OF OUR BIRDS 
4C7 
Fia. 103. 
TYPES OF THE PRINCIPAL GROUPS OF BENEFICIAL AND 
DETRIMENTAL ANIMALS PREYED UPON BY BIRDS- 
(^Beneficial?) MAMMALS. (^Detrimental) 
Those preying upon night-flying insects;— Those eating grains, birds or their e ggs i 
^ats. Those eating terrestrial and underground 3^ats, Mice, Gophers and Squirrels, 
inseas;—Shrews and Moles. 
HOARY BAT. 
FOCKET GOPHER. 
WHITE-FOOTED MOUSE. 
COMMON MOLE. THOMPSON'S SHREW. 
BATRACHIANS. {Beneficial.) 
Those preying upon detrimental insects 
ToadSj Tree-Toads. Frogs and Salamanders. 
, LEOPARD FROG. 
FISHES. (Beneficial.) 
Those suitable for food or for the food of 
/ood-fishes. 
PICKER Et..- 
SNAKES. (Detrhnentali) 
l.arge ones preying upon trogs toads, birds 
and their eggs;—most snakes over l8*or20 
inches long.. 
BLACK SNAKE- 
CRUSTACEANS. {Detrimentati 
Those building clay chimneys in meadows.(??) 
CRAY-FISH. 
SPIDERS, fBeneficial J 
'Those preying upon detrimental insect^ 
^FIDES. 
MYRIAPODS, fBen eficial. J 
Those preying upon detrimental insects. 
V '• . . 
mf i 
^ ff S V~ fsfi 
MJ))) 
AMERICAN EARWIG. 
