36 BULLETIN 862, U. S. DEPARTMENT OF AGRICULTURE. 
crab (Hexapanopeus angustifrons) which frequents the beaches there. 
One gizzard contained the claws and other remains of at least 30 of 
these crabs. When crawfish are eaten by ducks, small plano- 
convex masses of calcareous matter known as gastroliths, supposed 
to be used as material for a new exoskeleton after moulting, often 
are found, with the fingers or claws persisting in the stomach after’ 
other parts of the crawfish are digested. Small bivalved crustaceans 
(Ostracoda) had been taken by 38 of the pintails, sand fleas or beach 
fleas (Amphipoda) by 20, and sowbugs (Isopoda) by 5. 
INSECTS (INSECTA), 2.85 PER CENT. 
Beetles (Coleoptera) amounting to 0.93 per cent of the total food 
of the pintail, consisted largely of three families, the predacious 
diving beetles (Dytiscidae), water scavenger beetles (Hydrophilidae), 
and ground beetles (Carabidae). Others represented were the snout 
beetles (Curculionidae), leaf beetles (Chrysomelidae), leaf chafers 
(Scarabaeidae), crawling water beetles (Haliplidae), rove beetles 
(Staphylinidae), click beetles (Klateridae), flat bark beetles (Cucuji- 
dae), and tiger beetles (Cicindelidae). Besides these there were the 
fragments of many unidentified beetles and the larvae of aquatic 
species. - 
Flies (Diptera) found in the pintail stomachs consisted mainly 
of larvae and amounted to 0.85 per cent of the total food. The 
following families of flies were represented : Midges (Chironomidae), 
in 31; brineflies (Ephydridae), in 15; soldierflies (Stratiomyidae), 
in 8; craneflies (Tipulidae), 100), Oe honsefltes (Tabanidae), in 2; and 
unidentified fly remains in 10 shotncha, 
The larvae or nymphs, and a few adults, of dragonflies (Anisoptera) 
and damselflies (Zygoptera), together funmisined 0.44 per cent of the 
pintails’ food; bugs (Heteroptera), consisting chiefly of water boat- 
men Caddie) creeping water bugs (Naucoridae), and giant water 
bugs (Belostomatidae), amounted to 0.23 per cent; the larvae and 
lareal cases of caddisflies (Phryganoidea), 0.2 per cent: and other 
insects, consisting of a few grasshoppers (Orihioptern), ants and 
wasps (Hymenoptera), and Mayflies (Agnatha), totaled 0.2 per cent. 
MISCELLANEOUS ANIMAL FOOD, 0.4 PER CENT. 
The remains of small fish (found in 16 stomachs), a frog (Rana sp.), 
mandibles of a few marine worms (Nereis sp.), tiny water mites 
(Hydrachnidae), bits of hydroids (Hydrozoa), corallines (Bryozoa 
and Alcyonaria), and the minute, lime-incrusted, one-celled organ- 
isms known as Foraminifera, all were included in the varied bill of 
fare of the pintail. 3 
