Miscellaneous. 109 



MISCELLANEOUS. 



A Multicellular Infusorian-like Animal. 

 Jj)' Prof. Johannes Fkknzel, of Cordova (Argentine Ilopublic). 



After sending to the press a preliminary report upon my investi- 

 gations into the microscopic fauna of this locality I discovered, on 

 making a fresh examination of a small salt-water aquarium, a really 

 remarkable microscopic creature, exhibiting indeed many relations 

 to the Ciliata, but sharply separated from that group on the one 

 hand by its multicellular character, and on the other by its ■well- 

 differentiated alimentary cavitj^ witliout, however, being directly 

 referable to the Coelenterata, owing to the fact that only a sinc/le 

 layer of cells is present. 



For the investigation of the salt-pit fauna of this region I had pro- 

 cured a few litres of a solution containing about two per cent, of salts, 

 obtained from a salt-pit in the soutli of the province of Cordova. It 

 was some time before a few Flagellata &c. were developed among 

 decaying matter, and these presented so few noteworthy characters 

 that I abandoned my researches. On casually resuming my studies 

 I found a number of little creatures, of which I would here give a 

 brief description ; the animals were met with at the bottom as well 

 as upon the glass sides of the vessel, but not free-swimming. 



The external form is that of a tube, somewhat pointed iu front 

 and behind, and slightly flattened dorso-ventrally, so that it may be 

 termed bilateral. The ventral surface is Hat, the dorsal, on the other 

 hand, tolerably evenly arched, so that the transverse section is 

 approximately semicircular. 



The vcutral surface is clothed with delicate cilia, by means of 

 whicli the animal moves actively along, twisting about at the same 

 time like a snake or worm. The dorsal and lateral regions, on the 

 contrary, are not ciliated, but bear a sparser covering of short setae. 

 In front, nearer the ventral surface, we fiud an oral ojicnincj ; poste- 

 riorly, exactly terminal in position, an anal aperture of smaller size. 

 At the former opening longer and stouter cirri are placed, by the 

 active movement of which particles of food are whirled into the 

 mouth. 



A well-developed cuticle or similar firm dermal layer is wanting ; 

 nevertheless, as in the Ciliata, the membrane of the cells, or limiting 

 layer, is more strongly developed on the outer side, almost possessing 

 a double contour, though it is always very delicate. 



The wall of this tube-shaped organism is furnished by a single 

 layer of tolerably large, almost cuboid cells, all of nearly equal size, 

 leaving a cylindrical lumen, which is closely packed with foreign 

 bodies, such as particles of sand, bai-illi, diatoms, vegetable matter, 

 &c. This is the intestinal cavity, which commences iu front at the 

 mouth and terminates posteriorly at the anus. 



The cells are all more or less similar in structure, the difference 

 consisting, as already stated, in the fact that those of the ventral 

 side are ciliated on their free surfaces. In all cells the surface 

 which is turned towards the lumen of the intestine is also deKcately 



