94 PROCEEDINGS OF THE ACADEMY OF [Jan., 



tions which are most conspicuous at the anterior end, and these con- 

 tortions are of such a character that it is wholly impossible to say 

 whether a given point of the surface is protomerite or deutomerite. 

 From this end, moreover, little lobopodia were seen to arise and dis- 

 appear. 



In the case of a small gregarine from Lithohius, a very noteworthy 

 movement was seen. This expressed itself as a slight peristalsis, the 

 wave being evident at times on only one side. It was accompanied 

 by a flow, en masse, of the granules of the entocyte. This flow, start- 

 ing at the posterior part of the deutomerite, would pass forward until 

 it struck the septum. Here the granular mass was deflected backward, 

 the peristalsis being reversed at the same instant. In one case the 

 nucleus was carried forward and backward along with the granules. 

 This movement was seen both in animals that were progressing and 

 those which were not. It was displayed constantly, but was generally 

 very much faster when the animal was progressing. In one observa- 

 tion made, however, the gregarine showing this movement had its 

 progression suddenly checked by striking an obstruction, and here 

 the flow and peristalsis continued with unabated vigor. Frequently 

 when gregarines are pinched by passing through narrow places, or 

 when they bend, the entocyte is seen to flow. But in no other case 

 amongst the Folycystidea which has ever come under my notice was 

 the flowing anything like so free and extensive. These gregarines were 

 very favorable for a study of the movements of the entocyte, since the 

 number of granules was remarkably few and their flowing easy to 

 observe. 



A somewhat similar peristaltic movement was once seen in Tricho- 

 rhynchus pulcher Aime Schn. Here, the gregarine lying in one place, 

 the wave arose at the posterior end and passed forward. The move- 

 ments on both sides were not synchronous. It differed from the case 

 just described in that there was no reversal, the movement being con- 

 tinuously forward . 



The protrusion of the long tongue-shaped process by T. pulcher and 

 of the lobopodia by *S. spiroboli are not satisfactorily credited to activ- 

 ity of the myocyte. Such an action would appear to involve the spon- 

 taneous lengthening of relaxed fibres, which is scarcely possible. But 

 even if it did not, the form of the mj^ocyte, which is that of a fine-meshed 

 net, would not seem to lend itself to such movements. They would 

 necessitate an enormous elongation of a very small part of the system, 

 and would thus predicate a complexity of action which we could hardly 

 expect in so simple an apparatus. Without, however, desiring to preju- 



