Oxi/trichina.] THE INFUSORIA. 317 



Family XXL— OXYTRICHINA. 



This family contains all polygastric animalcules which 

 possess an alimentary canal with two separate orifices, 

 neither of them situated at the extremities — which have no 

 lorica, but are provided with setce, vibratile cilii, and non- 

 vibratile styles or uncini. These locomotive organs are 

 variously situated, and render the creature active. The 

 polygastric cells, disposed upon an alimentary tube, have 

 been demonstrated by Ehrenberg, and in Ceratidium only 

 are indistinct. The mouth and discharging orifice, ova- 

 like granules (at certain periods), and male organs (glands 

 and vesicles), are each seen in four genera. Complete 

 transverse and longitudinal self-division is observed in 

 three genera, but no gemmae or buds. Eyes have not 

 been detected. 



r brow without horns Oxytricha. 



Cilii and setae — no styles or uncini-^ 



L brow with horns Ceratidium. 



r with uncini — no styles Kerona. 



Styles, or uncini, or both ( with styles — no uncini Urostyla. 



(_ with styles and uncini Stylonychia. 



Genus CXXV. Oxytricha. The hatchet Animalcules sn'e 

 destitute of styles and uncini, and unprovided with horns. 

 The locomotive organs are cilii and setge, though the 

 latter resemble rigid hairs ; their movements are forwards 

 and backwards, often by impulses, creeping, swimming, 

 and climbing; all locomotion is effected by the vibration of 

 the former. In all the species polygastric cells are evident, 

 in five ova-like granules, in four male glands, and in five 

 round sexual vesicles. Transverse and longitudinal di- 



