164 DESCRIPTION OF \_Poli/gast> ica. 



the base of the double proboscis, before mentioned, and indicated by 

 a bright spot. The eye, which is placed near the mouth, implies the 

 existence of a sensitive system. Dujardin has been unable to detect 

 the double proboscis, and the connecting cords as described by 

 Ehrenberg, and consequently admits the existence of only one flagelli- 

 form filament. 



VoLvox glolator (M). The globe Anmalcules. — The creatures which 

 form these clusters are extremely minute. Each cluster is of neai'ly 

 a spherical form, and Tvill often contain within its younger clusters, 

 of a green colour, and smooth or even surface. ^Tien blue or red 

 colouring matter is mixed with the water, strong cuiTcnts may be 

 observed under the microscope ai'ound each globe, which, when in 

 motion, always proceeds with the same part foremost. 



Eig. 55 represents a large globe with eight smaller ones (termed by 

 Ehrenberg, sisters) within it ; each of them has a bright spot, which is 

 considered as an opening for the admission of water into the interior. 



Eig. 56 represents a section or piece of a globe, magnified 500 

 diameters ; it exhibits five single animalcules and a small cluster of 

 six young ones. They are attached to the lorica, and connected 

 together by five thread-like bands. Each creatui-e has a double pro- 

 boscis and the red eye. 



Eig. 57 represents a single animalcule, separated from its lorica, 

 and magnified 2000 diameters. Eound in shallow pools of clear 

 water, in spring and summer, at Ilampstead. 



The largest globes measure l-30th of an inch in diameter; the 

 smallest free swimming ones l-360th to 1 -240th. Size of a single 

 animalcule, 1 -3500th. 



M. Lam'ent describes two kinds of contained reproductive bodies 

 in this species, the one green and provided with vibratile cilia, the 

 other smaller, consisting of a transparent envelope (shell) which con- 

 tains a thick and red globular substance. The fonner he considers to 

 be gemmules, the latter oviform bodies, or ova ; which, however, he 

 has not yet seen imdergo development. (Institutes de la societe 

 PhUomatique, de Paris, 1848.) 



Ehrenberg notified the peculiar occurrence of living Rotatoria 

 within the globes of the Vokox glolator. Mr. John Williams has 



