new or little-known Infusoria. 215 



number, and arranged at tlie summit of the body in a single 

 broad bundle. 



The pedicle, which supports the body with its carapace, is 

 not much longer than the carapace itself. It is cylindrical, 

 slender, of uniform breadth, and furnished with a central axis 

 composed of a material different from that of the surface, and 

 apparently less dense. There is no enlargement of the 

 pedicle either at the spot where it joins the carapace or where 

 it is attached to the plant on which I observed the animal. 

 It terminates suddenly, without forming a disk to facilitate 

 fixation, such as is observed in nearly all the other species. 



As to the systematic position of Acineta livadiana^ it cannot 

 be confounded with any other known marine species. The 

 oval general form with the posterior part rounded is a very 

 rare phenomenon among the Acinetce, which, in general, have 

 a more or less conical form. There are only Acineta cothurnia, 

 Clap. & Lachm., and Acineta comjjressa, Clap. & Laclim., 

 which have also an oval form and the bottom of their cara- 

 pace rounded ; but it is not possible to confound the species 

 that I have just described with A. cothurnia, the latter having 

 the carapace at its upper part terminated obliquely ; and still 

 less with A. compressa, which, as indicated by its name, has 

 a strongly compressed form and the two corners truncated, 

 which is not the case in Acineta livadiana. 



The following are some measurements of the present 

 species : — 



millim. 



Length of the carapace 0-0256 



Maximum breadth of the carapace 0'0192 



Length of the peduncle 0'0320 



Breadth of the peduncle 0'0012 



The individual observed by me was attached to a branch of 

 Ceramium floating on the surface of the Black Sea near 

 Livadia (Talta). 



Acineta Saifulm. Mereschk. 1877*. 

 (PI. XII. fig. 11.) 



In a memoir published in Russian on the Protozoa of the 

 north of Russia I described a new marine species of Acineta 

 obtained from the White Sea. I will here give a translation 

 of the description and a copy of the figure, taken from my 

 Russian memoir. 



The carapace is elongated, regularly conical, and not at all 

 compressed ; its form resembles that of a reversed sugar-loaf, 



* " Studies on the Protozoa of Northern Russia," p, 69, pi. ii. fig. 11, 

 in Travaux de la Soc. des Naturalistes a St. Petersh.. 1877. 



