Dr. V. Sterki on a new Infusorian. 291 



jecting like a wall all round (external parenchyma), which 

 bears, at its free margin, a closed circlet of 15-20 larger 

 " cilia," which will be more particularly described hereafter. 

 Within, at the base of the wall, there is a series of smaller 

 finer cilia, about half the length of the former. The middle 

 part, which projects upwards like a hill, consists of softer 

 material, and possesses spontaneous movement. On one side 

 of this part, within the above-mentioned wall, there opens a 

 somewhat irregular peristomial cavity penetrating into the 

 soft sarcode as a simple sac-like depression. No separate 

 oesophagus or mouth is observable in it ; but this is easily 

 intelligible, because this part of the body is not enclosed by 

 any cortical layer, and the nutritive masses can consequently 

 get easily into the interior. In like manner neither cilia nor 

 an undulating membrane are to be observed on the peristome. 

 Here, as in lintinnus fluviatilis, all these structures are func- 

 tionally replaced by the portion situated between the peri- 

 stome and the middle line, which moves alternately forward, 

 and at the same time sideways, and then back again, con- 

 stantly oscillating to and fro, and thus acting like a cushion- 

 like lip or tongue-like organ. In this case it is a very inter- 

 esting and remarkable fact that we have here evidence of the 

 possibility of a spontaneous and voluntary movement of the 

 soft internal parenchyma, of which this part may well be said 

 to consist. 



The substance of the body is colourless or scarcely tinged 

 with pale yellow, transparent, with a few granules and food- 

 masses. Myophane bands, such as occur in the Stentorinse, 

 were not to be detected, any more than a serial arrangement 

 of the oil-drops in the external parenchyma. In the peduncle 

 also no differentiation into various parts was recognizable. 



In the interior of the body there is, near the posterior end 

 (leaving the peduncle out of consideration) , a single distinctly 

 recognizable elongate nucleus on the side opposite to the peri- 

 stome. In its posterior extremity, in many cases, a well- 

 marked, spherical, strongly refractive part was distinguishable, 

 probably the nucleolus — which is rendered more probable be- 

 cause I could detect nothing of the kind in the vicinity of the 

 nucleus. A contractile vesicle, apparently rather variable in 

 position and dimensions, occurs in the neighbourhood of the 

 peristome. In the anterior half of one specimen there were, 

 moreover, several rather large roundish " serous " spaces, 

 between which many smaller ones could be recognized — a 

 phenomenon which, as is well known, occasionally occurs in 

 many other species. 



I was unable to Ascertain the position of the anus 



