STUDIES ON CILIATE INFUSORIA.^ 



BY N. M. STEVENS. 



CONTENTS 

 Plates I-VI. 



I. LiCNOPHORA MACFARLANDI, SP. NOV 3 



II. BOVERIA SUBCYLINDRICA, GEN. ET SP. NOV 20 



These forms were discovered by Dr. F. M. McFarland 

 in the respiratory tree of Holothuria californica Stimp., at 

 Pacific Grove, California, in the summer of 1893. In June, 

 1898, the working out of their structure and general biology 

 was assigned to the author of this paper as a problem in 

 cytology. The number of new and interesting points which 

 came out in the course of the study seems to warrant the 

 present publication. 



The work on which the paper is based was done in the 

 Hopkins Seaside Laboratory at Pacific Grove, and in the 

 Histological Laboratory of Leland Stanford Junior Uni- 

 versity, between June i, 1898, and January i, 1900, under 

 the direction of Dr. McFarland, to whose suggestions and 

 cooperation is to be credited whatever of value the paper 

 may contain. 



My acknowledgments are due to the Directors of the 

 Hopkins Seaside Laboratory, Drs. Gilbert and Jenkins, for 

 the use of an investigator's room and for all possible labo- 

 ratory assistance and privileges during the summer of 1899. 



Technique. — The respiratory tree was removed from the 

 living holothurian, plunged into the fixing fluid, and later 



1 Thesis presented to the faculty of Iceland Stanford Junior University, May 25, 1900, 

 in candidacy for the degree of Master of Arts. 



[i] April 26, 1901. 



