FOOD HABITS OF MALLARD DUCKS. 
33 
TaBie II.—Items of animal food identified in stomachs of mallard ducks and the number 
in which found—Continued. 
Kind of food. 
Total number of stomachs examined 
CLASS Gastropoda (UNIVALVES)—Continued. 
Calyptreide. 
Crepidula convexa 
Crepidula fornicata 
Pyramidellide. 
Odostomia impressa 
Odostomia menestho trifida 
Odostomia sp 
Turbonilla sp 
Litorinide. 
Lacuna vincta 
Lacuna sp 
Litorina grénlandica 
Litorina irrrorata 
NL ULORUTONILON COS emer eee aes e ee sins Gale SS er ce eee ean es aan 
Litorina pailiata 
JOIN PUOB ROL ISS S85 So SSS Saab SCC A OEE a ee SE onetere eee egw are 
J ROI OES Ussos ab ates Sab SSC O pS ORDO Ee SS Tate Ses Shree tee ices eae sae 
Modulide. 
Modulus modulus 
Cerithiide. 
Bittium nigrum 
JAMO SOS Gis BOGS E Se BORON OO En Ae ee Sag arene eee ene 
Rissoide. 
Paludinella salsa 
Amnicolide. 
Amnicola limosa 
Amnicola olivacea 
Amnicola parva 
Amnicola peracuta 
Amnicola porata 
Amnicola sp 
Paludestrina sp 
Valvatide. 
VLU OLURSUILCEN Cems ep ae oe ico eee Nei aisle Ss eio oe een ees See 
Valvata tricarinata 
WALSTE DGS Ses So SC Re Ree eee 
Vaivata sp 
Viviparide. 
VAUD ON ORI TUL ENE CLL sixty eNotes, rae Sissi Sie Sees eae Soe Hear 
Campeloma indecisa 
Campeloma sp 
Ampullariide. 
Ampullaria sp 
Neritidee. 
NIVENIETILOATCC LLU LE Deen apr te a clea sist te oe rae Oe Shalala = cratava'slaiwiReioyaiae. sjoieie si sinns | 
SANG OTIRE COED, Jere os nee bic oee Abdo eed een ae sae soe panics saecseseae= 
Trochide. 
Margarites helicinus,. 
Se ee 
Common 
mallard. 
1,725 
Black 
duck. 
622 
Southern 
black 
duck. 
