STUDIES IN THE LIFE-HISTORY OF EUGLENA. 325 



(1) three to seven oblong, flattened chromatophores present, 



each with an uncovered pyrenoid in the center; 



(2) the periplast is more rigid than in many other forms studied 



so that the body does not show typical euglenoid move- 

 ment when in the active condition ; 



(3) flagellum about two thirds the body length; 



(4) paramylon bodies small and not very abundant. 



Gullet and Reservoir. 



This structure has been described and figured for many flagel- 

 lates, including Astasia ocellata and Euglena viridis (Khawkine, 

 1886); E. viridis (Wager, 1899); E. sanguined (Haase, 1910); 

 E. Ehrenbergii (Hamburger, 1911); Astasia levis (Belar, 1916); 

 Peranema (Hartmann and Chagas, 1910); Eutreptia (Steuer, 

 1904); Copromonas (Dobell, 1908); Menoidium (Hall, 1923). 



In E. agilis a somewhat funnel like depression is located at the 

 anterior end and leads directly into the gullet which curves as it 

 passes inward toward the side of the animal on which the stigma 

 is located. The reservoir seems to be in direct connection with 

 the gullet; it is asymmetrical in shape, the largest portion being 

 toward the inner side of the body (Fig. i). The vacuole system 

 in connection with the reservoir has not been made out in E. 

 agilis but in some of the larger species examined, E. polymorpha, 

 E. caudata, E. sanguinea and E. spirogyra, a series of small 

 pulsating vacuoles have been seen discharging their contents into 

 the reservoir along its periphery. 



The function of the gullet-reservoir system is not definitely 

 known. Khawkine (1886) suggested that it was used for the 

 admission of liquid food, giving as evidence the accumulation of 

 small granules of paramylon near the gullet when the animals were 

 fed potato starch in the dark. Kent describes observations made 

 on Euglena viridis kept in carmine suspension, where he observed 

 the passage of fine particles of the carmine into the body by way 

 of the gullet. Wager (1899) considers it an excretory system. 

 Rhodes and Kirby (Mss.) find that Hetronema, a related form, 

 lives on a diet of Euglena proxima, which they have observed 

 being taken in through a specially modified cytostome supported 

 by a horseshoe-shaped lip and two deeply staining pharyngeal 



