28 JOHNS HOPKINS UNIVERSITY MORPHOLOGICAL MONOGRAPHS. 



gave rather feeble, somewhat convulsive pulsations with local 

 (fibrillar) contractions ; the pulsations in some cases were pretty well 

 coordinated, but were more on the twitching kind. 



13. Three clubs were removed. The animal pulsated well, only 

 a little less strongly, perhaps. After a minute or two the fourth 

 club was removed. It pulsated almost immediately, perhaps thirty 

 seconds after the operation. It swam very well and pulsated feebly 

 five hours after the operation. 



14. One from jar (a) (Experiment 6) was operated upon. 

 When the first club was cut off there was a paralysis of pulsation 



I 



followed by a quick recovery. Cutting off the second club seemed 

 to stimulate pulsation, the third to diminish it; after cutting off 

 the fourth club it still pulsated. When placed in a large jar it 

 pulsated on the bottom, but not strong enough to swim. The 

 pulsations were fairly regular and sometimes seemed to occur in 

 groups of two, but these groups were not well marked. 



15. Another one from jar (a) was taken. One club was cut out, 

 upon which there was a very temporary paralysis followed by good 

 pulsations afterwards. The proboscis, as in all cases noticed, gave 

 active movements to this side and that side. These movements of 

 the proboscis were often very quick and definitely directed as if a 

 well defined stimulus were given. After the operation one pedalium 

 contracted so as to be at a right angle to the main axis of the bell ; 

 shortly a second pedalium also contracted. Placed in a small round 

 dish the animal swam actively. 



A second club was removed, and it swam as well as before. After 

 fifteen minutes it was not swimming but pulsating against the jar. 

 Upon stirring it a little it swam vigorously ten to fifteen strokes 

 and then stopped. It seemed weak and its movements appeared 

 not so definite, though this might be due to weakness. 



A third club was removed. The only change seemed to be 

 rather greater weakness. 



After about five minutes the fourth club was removed. Para- 

 lysis of pulsation followed. It had the power to contract its pedalia 

 when these were rather vigorously stimulated with a needle. It 

 also gave one feeble pulsation when so stimulated. 



16. The sensory clubs were removed from another. After removal 

 of the third one it still pulsated actively, but stopped completely and 

 apparently for good after the removal of the fourth club. Another 



