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there is some confusion existing between what is considered, for instance, 

 a filter (and or) suspension feeder. Rather than give all of the previous 

 definitions, most of which can be found in Yonge (1928) and Jorgensen 

 (1955), only the ones which apply to this study are presented. The feeding 

 types dealt with in the following discussion are 1) suspension feeders. 

 These animals are those which both propel and filter their food from the 

 surrounding waters, i.e. they may take food, both living and dead, from 

 the water by bringing this water into contact with their feeding mech- 

 anisms, and often filtering out this food, passing the remaining water out 

 of their systems. Their filters may be adjusted for various size food particles, 

 or else, the water currents may be such that only large particles or larger 

 animals are brought into contact with grasping mechanisms. Some of 

 these suspension feeders may actually feed on deposits, or at least on 

 soupy detrital material occurring just off the bottom, until unwanted 

 particles tend to clog the filtering apparatus to such a degree that more 

 energy is expended in getting rid of the unwanted material than in gaining 

 food. For this reason, suspension feeders are at their best advantage in 

 clear waters on a hard bottom. Type 2) discussed here is the deposit 

 feeder. Deposit feeders gain their food directly from the bottom sediments 

 or in the soupy organic layer on the surface of the sediments. In the rather 

 limited number of species of lamellibranchs, they may use palps, which 

 are highly developed sorting organs, or have long, prehensile inhalent 

 siphons for picking up living and dead material from the sediments. Other 

 invertebrates may be non-selective deposit feeders, such as holothurians 

 and most polychaetes ingesting the whole sediment, extracting the food 

 while the sediment is passing through the animal, and expelling the unused 

 inorganic material. 3) Predators or carnivores are those animals which 

 prey on or capture living food, particularly the more motile organisms. 

 Many large gastropods, certain asteroids, many crustaceans, and even one 

 group of lamellibranchs (Cuspidaria) fall into this group. 4) Algae feeders 

 and/or browsers are, in this paper, those animals which are primarily 

 herbivores, feeding either on diatom films, bryozoans, sponges, etc. on a rock 

 or sandy surface, or feeding directly on attached vegetation. 5) The 

 scavengers or carrion feeders feed primarily on dead flesh, although 

 may also be predaceous when carrion is not available. .Some animals which 

 fall into this category are certain Buccinid snails and many crustaceans. 

 Finally, there are the parasites, feeding directly on a host and eventually 

 killing it, and commensal organisms, which may feed on or depend upon 

 a host to get their food, without harming it. Other feeding types certainly 

 do exist, but are modifications of the above types and are not discussed here. 



