Dr. V. Sterki on a new Infusorian. 293 



like a hand, into about six divisions. I have seen this struc- 

 ture clearly and repeatedly and in different positions of the 

 animal ; so that there can be no doubt about it. Moreover 

 the observations were made on perfectly fresh and lively spe- 

 cimens, so that any division superinduced by pathological 

 conditions is excluded. In the sequel I had the opportunity 

 of observing nearly the same structure in Tintinnus fluviatilis, 

 St., only it appeared to me that the points were rather more 

 numerous and also finer and smaller. Each of these " cilia " 

 gradually turns a little upon its axis, so that the surface 

 approximates to the circular zone of insertion. In repose 

 they all stand straight out, or still more bent in towards the 

 axis of the body, forming a dense tuft ; but they do not appear 

 so much curved, or even almost angularly bent, as those of 

 T. fluviatilis. 



As already indicated there is within the cilia just described, 

 at the base of the wall-like supporter of the latter, a second 

 series of short fine cilia, which, so far as can be seen, are 

 neither particularly flattened nor divided into filaments. 

 They may perhaps be homologous with the paroral cilia of 

 the Oxy trichina? *. Whether T. fluviatilis possesses the 

 second inner row of cilia I do not know ; at any rate I have 

 not yet seen them. 



In general the movement of the animal is but small, and is 

 limited in the case of the specimens inhabiting tubes to a 

 rather slow protrusion and a by no means rapid retraction, 

 by the elongation or abridgment of the peduncle, which may 

 be entirely withdrawn into the body. The forward move- 

 ment is of such an extent that the anterior large cilia protrude 

 from the tube and can move ; but they never separate widely 

 from each other. Frequently we meet with specimens of our 

 species without tubes, which attach themselves to the object- 

 bearer (or to any object upon it) without a peduncle, and, indeed, 

 very often with the anterior part turned upwards. Here, as 

 in a lateral view, the animals may be observed very conveni- 

 ently, as they usually remain quite quiet. Frequently no 

 cilium moves for a long time ; then a single one slowly bends 

 outwards (peripherally) , and strikes rapidly and, as it were, 

 convulsively inwards ; then one or another in different parts 

 will act in the same manner. Simultaneous movement of all 

 the cilia, or of a considerable portion of the series, is more 

 rarely observed ; and especially there are no simultaneous or 

 undulatory movements passing through the series. In the 

 open water the animals swim pretty rapidly by means of the 



* Loc. cit. pp. 37, 38. 



