314 WILSON GEE 



mucus gradually exhausts the region. As is usual in fatigue, 

 strong stimuli may produce reaction for some time after weak 

 ones have failed. The fatigue thus caused usually lasts only 

 two to five minutes. After this period has elapsed the fatigued 

 region is frequently as ready to take food as before — provided 

 the animal is still hungry." 



FEEDING REACTIONS OF CR1BR1XA XAXTHOGRAMMICA 



The responses involved in food taking in Cribrina are much 

 the same as those so excellently described by Jennings for 

 Stoichactis helianthus. If a piece of fresh oyster is given the 

 tentacles of a hungry Cribrina these immediately adhere to the 

 meat, and bending over with it, hold it tightly against the 

 surface of the disk. A depression of the disk takes place in 

 the region of the food, and in this way the mouth opening is 

 brought nearer to the piece of oyster. This opening in the 

 meanwhile has become enlarged and the bladdery lobes of the 

 stomodaeum are extruded towards and arOund the food. The 

 tentacles release their hold, and the food is taken into the gas- 

 trovascular cavity by the muscular action of the stomodaeum. 

 Depending very largely upon the size of the piece of meat, 

 either a part or the whole of the disk and tentacles may con- 

 tract during the feeding reaction. For a small piece, usually 

 only a portion of the disk is involved in the food taking if the 

 anemone is of fair sized proportions. 



It occurred to the writer that there might be some way of 

 securing the same effect on the metabolism of the anemone as 

 is produced by the food without the muscular effort incident to 

 food taking. Thus the factor of muscular fatigue as such could 

 be eliminated. Wyeth's beef juice, for which the manufactu- 

 rers claim "that it contains all the albuminous principles of 

 beef in an active and soluble form" was the first substance 

 used. A dilution of this, two parts of beef juice to eight parts 

 of sea water, was forced by means of a pipette into the gastro- 

 vascular cavities of several anemones. It was found impossible 

 to prevent an ejection of this material to a certain extent by 

 the contraction of the anemone, and the consequence was a 

 diffusion of the beef juice over the tentacles, with an immediate 



