Vol. XXVII. September, 1914. No. j 



BIOLOGICAL BULLETIN 



THE FOOD AND FEEDING HABITS OF FRESHWATER 



MUSSELS. 1 



WILLIAM RAY ALLEN. 



THE FEEDING HABITS OF MUSSELS. 



CONTEXTS. 

 Introductory 127 



The Cilia and their Action 128 



Scope and Nature of Investigation 129 



Material 129 



Anatomy and Previous \York on the Function of the Cilia 129 



Observations: 



The Ciliary Streams 131 



The Function of the Mucus 133 



Conclusions on the Function of the Ciliary Currents 134 



The Selection and Rejection of Food Particles 134 



The Rate of Siphoning 135 



Digestion 135 



The Crystalline Style . . 136 



Food Materials 137 



Bibliography 139 



INTRODUCTORY. 



With the increasing commercial demand for mussels and the 

 rapidly diminishing supply we shall have need for all the available 

 information concerning their life history. Lefevre and Curtis 

 ('12) have done a great deal toward solving the problems which 

 beset artificial glochidial infection. Much may still be learned 

 concerning the practicability of artificial feeding, the nature of 

 their enemies and of their diseases. 2 



1 This paper is the result of observations made at the Indiana University Bio- 

 logical Station, at Winona Lake, Indiana, under the direction of Prof. Will Scott 

 It forms contribution No. 130 of the Zoological Laboratory of Indiana University. 



An important obstacle to their successful cultivation is offered by the pollution 

 of streams. Searches which I made on several occasions in a certain section of the 

 Mississinewa river, into which oil and salt water from oil wells, and sewage from a 

 paper mill are poured, failed to produce a single living mussel, although there was 

 an abundance of empty shells. At this point, during the dry season, great school? 

 of fish take refuge in the shallow tributaries which are freer from pollution. 



127 



