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BULLETIN 720, U. S. DEPARTMENT OF AGRICULTURE. 



Table II. — Items of animal food identified in stomachs of mallard ducks and the number 



in which found. 



Kind of food. 



Common 

 mallard. 



Black 

 duck. 



Total number of stomachs examined 



SUBKINGDOM CCELENTKRATA. 



Aleyonana (sea fans) 



Hydrozoa (hydroid) 



SuBKiNGDOM NEMATHELMINTHES. 



Gordiidae (hairworm) ; 



SUBKINGDOM MOLLUSCOIDA. 



Phylactolaemata (fresh- water bryozoa) 



SUBKINGDOM ECHINODERMATA. 



Echinoidea (sea urchin) 



SUBKINGDOM ANKTULATA, 



Unidentified annelid 



Lumbricomorpha (earthworm) 



Nereis sp. (marine worm) 



SUBKINGDOM ARTHROPODA. 

 Class Crustacea (Ckustaceans). 



Unidentified. 



Order OSTRACODA. 



Bivalved crustacean, unidentified . 

 Candona sp 



Order COPEPODA. 



Water fleas . 



Order CIRRIPEDIA (Barnacles). 



Balanus amphitrite. 

 Chthamalus fragilis . 

 Unidentified 



Order AMPHIPODA. 



Unidentified 



Gammaridae (sand-fleas). 



Gammarus annulatus 



Gammarus locusta 



Gammarus marinus 



Crammarus sp 



Podoceridse. 



Amphithoe rubricata 



Grubia compta 



Photidffi. 



Microdeutopus gryllotalpus. 

 Orchestiidae. 



Hyalella azteca 



Hyalella dentata 



Hyalella knickerbocfuri 



Orchestia grillits 



TaUtrua megalophthalmus . . 



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