UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



ZOOLOGY 



Vol. 11, No. II, pp. 197-305, 13 text figures. December 9, 1913 



THE BEHAVIOR OP LEECHES WITH 



ESPECIAL REFERENCE TO ITS 



MODIFIABILITY 



A. THE GENERAL REACTIONS OF THE LEECHES DINA 



MICROSTOMA MOORE AND GLOSSIPHONIA 



STAGNALIS LINNAEUS 



B. MODIFIABILITY IN THE BEHAVIOR OF THE LEECH 



DINA MICROSTOMA MOORE 



BY 



WILSON GEE 



CONTENTS p^Qj, 



The General Reactions of the Leeches Dina microstoma Mooke 

 AND Glossipho7iia stagnalis Linnaeus. 



L Introduction 199 



II. Resume of literature 199 



III. Description of material 206 



IV. Categories of movements in leeches 208 



1. Basis for classification 208 



2. Random movements 209 



3. Looping response 210 



4. Swimming response 211 



5. Undulatory respiratory movements 212 



6. Righting reactions 214 



V. General responses to stimuli 216 



1. Formation of collections 216 



2. Food of leeches 217 



3. Feeding reactions 219 



4. Sensitivity to various stimuli 221 



5. Reactions to light 223 



6. Effect of currents 227 



7. Chemotaetic responses 229 



8. Reactions to gravity 230 



9. Influence of heat 231 



10. Thigmotaxis 232 



11. Ability to withstand desiccation 232 



