AUTHOR'S ABSTRACT OF THIS PAPER ISSUED Reprinted from THE JOURNAL OF EXPERIMENTAL 



BY THE BIBLIOGRAPHIC SERVICE OCTOBER 6. ZOOLOGY, Vol. 24, No. 2, November, 1917 



THE COMPARATIVE PHYSIOLOGY OF SYNAPTULA 

 HYDRIFORMIS (LESUEUR) 1 



J. M. D. OLMSTED 



TWO FIGURES 



CONTENTS 

 Introduction 333 



I . General physiology 334 



1 . Locomotion 334 



2. Feeding and digestive movements 339 



a. Effect of change of temperature on intestinal pulsation 342 



b. Effect of .chemical agents on intestinal pulsation 342 



3. The effects of external stimulation 345 



4. Other muscular activities 347 



a. Blood vessels 347 



b. Gonads 347 



5. Bacterial parasites 347 



6. Summary of Pert 1 347 



II . Sensory physiology 348 



1. The effect of deforming pressure 348 



a. Historical 348 



b. Observational 349 



2. The effect of gravity and of vibrations 353 



a. Historical. 353 



b. Observational 355 



3. The effect of light ., 358 



a. Historical 358 



b. Observational 359 



4. The effect of heat 362 . 



a. Historical 362 



b. Observational 363 



5. The effect of chemical agents 365 



a. Historical 365 



b. Observational 367 



6. General discussion 374 



INTRODUCTION 



Two varieties of Synaptula hydriformis (Lesueur), red and 

 green, are found at Bermuda in approximately equal numbers. 

 All gradations between these two colors are present, and there are 



1 Contributions frtm the Bermuda Biological Station for Research. No. 74 



333 



