The President's Address. By the Rev. W. E. Ballinger. 185 



The apparatus, as far as it is needed to reveal its purpose, is 

 before you* 



My earliest and continuous difficulty was to find specimens for 

 study. 



As in former instances, I determined first to follow out the 

 morphological details separately, and if possible exhaustively ; and 

 to fix on a given organism with all the details of its form known, 

 from one stage to another, until I had been able to trace it from its 

 earliest to its latest condition. 



The first step was a careful measurement of its visible body 

 sarcode. The body was of sub-oval shape, with a lenticular form 

 on the upper and under surfaces. 



The general appearance of the body alone is seen in figs. 1, 2, 

 3, plate IV., and on the measurement of twenty-five forms I 

 obtained an average length of the 1/10,000 of an inch, and a 

 breadth of 1/19,500 of an inch. 



But when closely and carefully examined with a 1/25 oil lens, 

 it presented the remarkable phenomenon of an organism so minute, 

 with no less than six flageUa, each one of which is nearly three 

 times as long as the long diameter of its body. 



It was soon evident that its movements were extremely varied, 

 and some of them entirely unlike anything I had hitherto seen. 



A not uncommon mode of locomotion was that of simple 

 swimming, as seen in fig. 1, plate V., where the anterior and 

 posterior flagella were in vigorous action, and the remaining four 

 either trailed or participated but slightly in the direction of 

 motion. 



But a movement quite as often resorted to, was much more 

 beautiful. The organism came to momentary rest much in the 

 attitude seen in fig. 4, plate V., and fig. 10, plate IV., when by a 

 sudden movement of the whole group of flagella, a series of wave- 

 hke leaps, reminding one of the movements of a shoal of porpoises, 

 ensued, and was continued for from ten to fifteen undulations. 



To actually make out the flagella and their movements required 

 considerable " penetration " as well as the most delicate definition. 

 A fine homogeneous 1/8 of Zeiss's greatly helped me in this 

 matter ; but at the last I reaped my most perfect results with the 

 new 1/6 of 1'50 N.A. Indeed, I had the glass made with this 

 special object ; and the need of it will be seen more fully when I 

 describe the essentially unique and characteristic movement of this 

 monad. 



In previous forms which I had studied, both with Dr. Drysdale 

 and alone, I had observed and described forms that anchor the body 

 by means of one or more long trailing flagella, which flagella are 



* This will be illustrated iu a subsequent part of the Journal. 



