P/titodmaea] THE INFUSORIA. 395 



species red eyes are present, and beneath these organs only 

 is nervous matter apparent. 



The genera are disposed as follow: — 



r proboscis anj foot processes present Callidina. 



Eyes absent. ( , i rotatory organ petlicled Hydrias. 



1 no proboscis or J ■" 



t '>°^n-'il^e processes \ ^^^^^^^^ ^^^^^^ ^^^ p^^^^,^.^, Typl.lina. 



, ^ , . . ,., r toes two .... Rotifer, 



loot li.aving horn-like J 



processes |^ toes three .. Actiuuius. 



Eyes present. 



two frontal \ 



foot without horn-like processes, 



Monolabis. 



toes two 

 two cervical , Philodina. 



Genus CLXXVIII. Callidina. I'/ie becniiij'ul Rota- 

 lorial Animalcule is characterized by wanting visual organs, 

 and by possessing a proboscis, and a foot, furnished with 

 processes resembling horns. The vibratile, or rotatory 

 organ, is double, but not pedicled ; anteriorly is a thickly- 

 ciliated proboscis. The furcated foot has two elongated 

 toes, four little horns or processes, and six points. Two 

 muscles for moving the foot are also visible. The oeso- 

 phagal head has two jaws, with numerous delicate teeth. 

 The filiform alimentary canal has a bladder-like expan- 

 sion posteriorly, but is not provided with glands; it is 

 surrounded by a granular and cellular mass, whose func- 

 tion is unknown : Ehrenberg thinks it is connected with 

 reproduction ; an ovarium, with single large ova, is seen ; a 

 little spur-like process, projecting from the neck, may be 

 a respiratory tube; no indication of a nervous system is 

 observable. 



688. Callidina elegans. The graceful Callidina. — 

 Body spindle-shaped, crystalline ; rotatory organs, or 

 wheels, small, /''gs. 470 to 472 represent this animalcule 



