Volvorina.] infusokial animalcules. 159 



Synceypta voIvox. Body of an oval form and green colour, with 

 whitish rays in the centre. Found generally in water drained 

 jEi'om Conferva. Size 1 -2880th; ditto of a clustered globule in its 

 crystalline tunic, hardlj^ exceeding l-570th. 



This berry-like cluster of animalcules, when rolling through the 

 water, is a beautiful object for the microscope, and, with the aid of a 

 little indigo, the numerous currents it creates are readily perceived. 

 The usual appearance of the clusters, as viewed under the microscope, 

 and amplified 260 diameters, is given at fig. 45. Fig. 44 represents a 

 cluster magnified 400 times, and fig. 46 a cluster as viewed by 

 Ehrenberg, in its simplest state, wlien about to sever into four. 



Genus Syntjka. TJie ray globe Animalcules are characterized by 

 being destitute of the eye, but pro\'idcd with a filiform tail, which is 

 attached either to the base of its own lorica, or to the centre of the 

 cluster to which it belongs. The general envelope is a gelatinous 

 substance of a spherical form, and fitted up into as many compart- 

 ments, or cells, as there are individuals in its little community. From 

 out of these cells they can severally stretch themselves a considerable 

 <iistance, whilst they continue fastened, in the manner before described, 

 by the extremely delicate and extensible tail. 



S. uvella. Composed of oblong corpuscles, of a yellow colour ; 

 capable of being stretched forth fi-om their cells to three times their 

 natural length, by means of the extensible tail. The cluster has the 

 form of a mulbeny, and its motion is a rolling one, like that of the 

 Volvox glohator. Figiu'e 50 exliibits a cluster magnified, and figure 

 51a portion of a cluster, to show the manner in which the tails of 

 the animalcules are inserted in the common envelope. This species, 

 along with Syncrypta and Uroglena volvox, may often have been con- 

 founded with Uvella virescens. Length of body, exclusive of tail, 

 1 -700th; diameter of cluster, from l-190th to l-280th. 



Genus TJkoglena. Tlie globe Animalcules, with ray and eye. — This is 

 the first genus of the family Volvocina, wliich is distinguished by the 

 possession of both the eye and tail. It is also a sort of compound 

 animalcule, living in clusters under a common covering or mantle 

 (laeerna), which is apportioned into cells for the accommodation of 

 the several individuals. Self-division takes place simply and equally 

 in these individuals, whilst remaining in their clustering condition. 

 Within the mantle they are placed at uniform distances from each 



