108 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



may be mentioned. Twelve species have been identified from the birds 

 represented in our tabulations, the total number of determinations 

 being 42. Slugs were identified three times, but our findings in this 

 respect probably are not representative since in Great Britain it is 

 said that : " Every kind of slug and snail is eaten greedily by black- 

 birds, thrushes, chaffinches, and in fact by many species of birds." 

 (Cooke, Cambridge Nat. Hist., vol. 3, p. 58, 1895.) With regard to 

 highly colored shells, such as Pec fen. conjectured by Wallace to be 

 protected, it may be said that our table shows 193 records for Pecten 

 and the Biological Survey has been called upon to make a special study 

 of damage to the scallop industry by wild fowl in the vicinity of 

 Marthas Vineyard, Mass. Teredos were identified from the stomachs 

 of four Bachman oyster-catchers and of one egret. 



It should be remarked that the very large number of records of 

 Ostreidae in the tabulations is due also to a special investigation of 

 the bird enemies of Ostrea lurida. The high records for Tellinidae 

 {Macoma, especially) and Paphiidae (Paphia sfaminea) are chiefly 

 by-products of this same study. The large numbers of identifications 

 for such dominant families as the Mytilidae. Nassidae, Columbellidae, 

 and Litorinidae among marine shells and Aninicolidae and Lymnae- 

 idae among fresh-water ones, need no explanation. 



Numl)er of identifications, 11,771; percentage of identifications 

 among those of all animals, 4.9583 ; percentage of species in this 

 phylum among the whole number of animal species known, 10.8828. 



Other enemies. — Mollusks are preyed upon to an important extent 

 by very many marine fishes, as well as by most of the rays and sharks ; 

 among these being numerous forms specialized (as by possession of 

 the pavement-like pharyngeal dentition) to feed upon shell fish. For 

 such fishes as the haddock, cod. wolfiish, and flounders they are a 

 staple food. Field found razor-clams in 4 per cent of 388 stomachs 

 of the smooth dogfish {Musfelus canis) ; and in 3.68 per cent of 

 516 stomachs of the summer skate {Raja eriuacea). The same author 

 found mollusks of various kinds in 17.64 per cent of the stomachs of 

 306 cunners {Tautogolabris adspersus) , and in 27.2 per cent of those 

 of 33 toadfish (Opsanits tait). Some of the marine fishes are known 

 to be enemies of certain specially defended mollusks ; as predators on 

 Crepidida, the scup, tautog, swellfish and toadfish may be mentioned ; 

 upon chitons, the haddock and flounders {Pleuronectes) ; and upon 

 Eolis and other nudibranchs, the cods, gurnards and flounders. 

 Cephalopods, especially squids, arc a favorite food of many of the 

 highly predacious fishes as the sharks, rays, bonito. swordfish, blue- 

 fish, mackerels, pollock, and haddock. It would be easy to compile a 



