122 PROCEEDINGS OF THE ACADEMY OF [PaRT I 



It is not likely that these modified elements should be considered 

 as the principal agents in the capture of food. Rather must we 

 think that the large surface displayed by the cup with its velum- 

 like borders has the function of a net; I have very often observed 

 small nutritive particles to be thrown, or rather to get caught on 

 the surface of the expanded cup; and suddenly, when it hardly 

 touches the net, a vacuole is formed, inside which the microbe 

 (most frequently microbes were the normal food) violently struggles 

 for a time, then suddenly collapses, as if killed by some poisonous 

 substance. The food-vacuole then glides along the velum and 

 finally disappears inside the body. 



The nucleus, spherical and with a big central caryosome, is very 

 distinctly seen, in the hind-part of the body. There is only one 

 contractile vesicle, not far from the nucleus; some other vacuoles, 

 however, are at times visible, either containing food-particles or 

 not. 



Phenomena were not observed concerning the division of the 

 body, but I have frequently met with individuals in the naked 

 state, which either resulted from an act of division, or, in a ma- 

 jority of the cases at least, had left their envelope to take to a swim- 

 ming existence. Their appearance is quite characteristic (Plate VI, 

 figs. 17, 18), nearly that of a mandolin, whose handle would be 

 represented by that peculiar "trunk" we have spoken of; but then, 

 from this very extremity where the small blue granule is still to 

 be seen, starts now, not a rigid thread, but a true flagellum, which, 

 beating normally, draws the animalcule forward in a rapid course; 

 the functions, indeed, of the thread have changed, and have be- 

 come those of a normal flagellum. 



As for the other flagellum, which we looked on formerly as the 

 principal one, it is now seen to start from the posterior, slightly 

 pointed extremity of the body, and immediately curves upward, 

 describing an arc whose tip becomes lost behind the body, near the 

 base of the trunk; this bow-like curvature seems at first sight to 

 dehneate the very contour of the body (Plate VI, fig. 1"), which 

 fact gives the little being a very peculiar appearance. 



After swimming for a time, the little Flagellate comes to rest, 

 it sets itself down on the surface of a Zygnema-thread, and firmly im- 

 plants itself there by its posterior pointed extremity; and hardly 

 is the contact effected when a small root begins piercing the jelly 

 (Plate VI, fig. 19), growing longer and longer, till after a few min- 

 utes it reaches the solid wall. 



