Vo>'ticelUna.'] INFCSoriai animvlctles. 533 



by Schrank, under the title of V. monadica, because at this perio(i 

 the stems do not contract spirally, as in tlie old ones. From some of 

 the specimens observed by Miiller, it is evident that they are also 

 produced by buds. 



The next method of propagation is by a division of the parent. 

 When this is to be effected longitudinally, the bell increases in 

 breadth ; a separation then commences, and two circles of cilia ara 

 formed ; the body of the animal then di\'ides, and other cilia grow 

 around the dome of the bell ; by constantly whirling, one or both of 

 the bells separate from the stem, and swim about, in which condition 

 they have been classed as a distinct gonas, under the name Urceolaria. 

 Should it happen that both the bells are twisted off, the stem re- 

 mains stationary, and docs not contract aftei-wards, or produce a new 

 bell. The most striking peculiarity which next presents itself is, 

 that the end formerly attached to the stem swims foremost, and from 

 the other extremity proceeds the new stem ; before, however, this is 

 effected, it changes its form, and sometimes buds out, or separates ; 

 the latter is the genus Eclinsa of Schrank, and the former, with the 

 small protuberance, Rinella of Bory St. Vincent. If the creature 

 retain its bell-shape, be not inverted, and exhibit the lower cilia, it 

 fomis the genus Kcrohalina of the latter naturalist, and when all the 

 cilia are invisible, then it forms his genus Craterina. Again, it con- 

 stitutes the genus Urceolaria, when the anterior cilia are alone 

 observed. Besides those already mentioned, there are many other 

 changes in its form ; sometimes it sti-etches itself out in length, and 

 becomes cylindrical, so that it is readily mistaken for a species of the 

 genus Enchelys ; in this condition, one or both ends bend themselves, 

 while it is swimming past a hard body; finally it separates trans- 

 versely in twain. 



The next method of propagation is by the formation of buds, and is 

 common both to the animalcules with, and to those without, a stem. 

 During this process it passes through a variety of shapes, moves 

 briskly in the water, and forms the genus Ophrxjdia of Bory St. Vin- 

 cent. Ehrenberg has divided this species into two varieties, founded 

 on the shape of the bell ; when they are nearly globular, he calls 

 them V. campanxdata ; when pointed, 'N . pyriformk. 



V. ineta. — Body ovate, conical, campanulate ; frontal portion 



