INFUSORIA. 51 



Pandorina BORY (in part), EHRENB. Animal without eye-point 

 and tail, furnished with a vibrating flagellum, a simple urceolate 

 lorica, by spontaneous internal division resembling a mulberry. 



Sp. Pandorina morum, Volvox morum MUELL. Infus. Tab. in. fig. 14 16, 

 EHRENB., Infimonsth. Tab. n. fig. 33. 



Gonium MUELL. Animals without eye-point and tail, by spon- 

 taneous division conjoined in a common quadrangular flat envelope. 



Sp. Gonium pectorale MUELL. Infus. Tab. xvi. fig. 911 ; EHRENB. Tab. 

 in. fig. i. 



\_Synura EHRENB. (Tab. III. fig. 9.) an uncertain genus], 



Chlamidomonas EHRENB. Animal with eye-point and double 

 flagellum, without tail, included in an urceolate envelope, either 

 simple or multiple from spontaneous division within the common 



covering. 



tt 



Sp. CMmidomonas pulvisculus, Monas pulvisculus MUELL. Infus. Tab. I. fig. 

 5. 6; EHRENB. Infusionsth. Tab. in. fig. x: represented by authors as in 

 part the green matter of PRIESTLEY. These animalcules were long ago 

 observed by LEEUWENHOECK ; see Sevende vervolg der Brieven, 1702. No. 

 142, p. 402. 



Volvox L. (exclusive of several species) Animalcules with eye- 

 point and single or double flagellum, included in the surface of 

 a globular envelope which rolls on its axis : there are often smaller 

 lobules (gemmce) within the large one 1 . 



Sp. Volvox globaior L., LEEUWENH. Sevende vervolg der Brieven, No. 122, 

 p. 156, fig. 2 ; KOESEL, Ins. in. Tab. ci. fig. 1-3 ; MUELL. Infus. Tab. ill. 

 fig. 12-13; EHRENB. Infusionsth. Tab. iv. fig. i. DUJARDIN, Inf. PL iv. 

 fig. 30. Globe-animalcule; a small green globule, as much as J line in 

 size, and hence visible to the naked eye as a fine grain of sand ; in 

 marshy water. Tliis form was first discovered by LEEUWENHOECK. On the 

 surface of the globule minute warty points are seen ; these are the individual 

 animalcules or monads of -L line. Within the globule smaller globules 

 are developed, which occasionally rotate within the large one until it 

 bursts and dies away 2 . 



1 [See F. COHN'S paper in SIEBOLD and KOELLIKER'S Zeitschrift fur wissenschaftliche 

 loologie, Band iv. p. 77, &c. for reasons why the Volvocina ought perhaps, as Von 

 IEBOLD and others believe, to be classed amongst Alyw.] 



[ 3 For an account of the development and encysting of individual monads of the 

 ay, of a size nearly as large as that of a young colony, see STEIN'S Infusionsthiere, 

 ;. pp. 45 46. When the full size has been attained the cyst thickens into regular 

 processes, giving the form which Ehrenberg has described as a distinct species, 

 7 olvox stettatus. These large encysted volvoces are for the continuation of the species 

 the ordinary individuals of the colony have perished.] 



42 



