JOURNAL OF ANIMAL BEHAVIOR 



Vol. 1. 



JULY-AUGUST, 1911. 



No. 4. 



HABITS AND REACTIONS OF THE CILIATE, 



LACRYMARIA 



S. O. MAST 

 Gaucher College, Baltimore, Maryland 



EIGHT FIGURES 



INTRODUCTION 



Lacrymaria ' is among the most interesting of living beings 

 owing primarily to its phenomenal power of elongation, its 

 wonderful elasticity and its great freedom of movement. 



C-. 



-0.1 mm. 



Figure 1 — Camera sketch of a living specimen of Lacrymaria. v. contractile 

 vacuoles; n. macronucleus; n'. micronucleus; c. oral cilia; o. oral knob; 

 a. symbiotic algae; 1. lines showing arrangement of the body cilia; mm. pro- 

 jected scale. 



Figure 2 — Camera sketch of an individual with the neck partially extended; cilia 

 not represented. Ihis specimen was killed with Worcester's fluid for protozoa. 

 I found it impossible to kill these creatures without marked contraction of 

 the neck. 



It is a Spindle shaped ciliate about o.i mm. long and 0.02 

 mm. in diameter. At one end there is a knob-Hke projection 

 on which the mouth is situated. This projection is bordered 



