K 



* 



* 



i 





Dr. A. G ruber on Protozoa. 319 



I animal, but one of them is placed horizontally. This is pro- 



bably due to the fact that the hinder part of the body, haying 

 assumed the rounded form, lias suffered a displacement of its 

 inner parts. It is remarkable that I could not succeed in de- 

 tecting the nucleoli. 



The ciliation is that characteristic of the genus Stichotricha. 

 I do not enter here into such details with regard to it as I have 

 already done elsewhere*, but confine myself to describing the 

 particularly prominent cilia. There are, in the first place, the 

 three long, stout, somewhat curved cilia at the extreme summit 

 of the neck, which are followed by the peristome with its regu- 

 larly arranged row of cilia. At the posterior extremity of the 

 peristome there is the fine membranous seam (see fig. 7) 

 which is here much more distinct than in Stichotricha social is 

 for example. It stands much further out from the neck, and 

 thus forms a sort of frill, such as has frequently been described 

 in other Infusoria. 



On the neck we see, further, the separate rigid setse stand- 

 ing regularly wide apart, as in the other Stichotrichce. Be- 

 sides these, flexible cilia, arranged in rows, cover the body, 

 although here, on account of the carapace, they are difficult to 

 observe. They are most distinctly perceptible at the posterior 

 end of the Infusorian, where they also present remarkable pecu- 

 liarities. Thus they can act alternately as cilia and as pseudo- 

 podia. In the former capacity they move in the well-known 

 manner, beating to and fro ; in the latter they serve to attach 

 the body to the carapace, to which they adhere like the pseudo- 

 podia of a monothalamous Ehizopod. The posterior end of 

 the Stickotric/ia is, in this case, not rounded off, but drawn 

 out into irregular lobes ; and these conditions may follow one 

 another alternately and quickly— a further proof of the ana- 

 logy (in this case identity) of the cilia and pseudopodia. 



Stichotriclia, of course, propagates by division ; and then for 

 a time there are two individuals in the same capsule. One 

 portion wanders forth and immediately secretes a new capsule, 

 either at a distance from the original one, or, should circum- 



stances be favourable, in its vicinity. In the latter way large 

 aggregations of Stichotrichce are gradually produced. The 

 intertwined flaskets, from which the long necks of the Infu- 

 sorians look forth, present a pretty appearance. 



I found Stichotricha iirnula at the surface of the water in 

 a small glass vessel in which, for a particular purpose, I had 

 mixed fresh water with artificial sea-water. The latter was 

 obtained from our marine aquarium, the former from the spring- 

 conduit; so that there can hardly be any doubt that the 



* u Neoe Infusorien/' Zeitschr. fur wis?. Zool. xxxiii. 



