Euchianidota.] T HE INFUSORIA. 381 



and Squamella the latter organ only in Metopidia, Lepa- 

 della, and Mastigocerca. They do not carry their ova 

 externally. Traces of a vascular system are seen in two 

 species of Euchlanis, and perhaps also the gills in Dino- 

 charis, and the respiratory tube in Salpina and Euchlanis 

 must be included. The nervous system is indicated in 

 ten genera by the presence of red visual points, whose 

 situation and number are useful to establish generic cha- 

 racters ; an evident cerebral ganglion (as a nervous layer to 

 the eyes) is found in Euchlanis, Monostyla, Mastigocerca, 

 and Salpina. The genus Lepadella developes itself oc- 

 casionally in such myriads, in stagnant water, as to give 

 a whitish turbidity to it. 



The genera are disposed as follow : 



No eyes, foot furcated ........................................ Lepadella. 



f t lorica depressed .................. Monostyla. 



styliform lorka prismatic .................. Mastigocerca. 



(cervicaT)i f lorica gaping beneath ............ Euchlanis. 



f foot ,\ , , f lorica horned ..... Salpina. 



furcated ] lorica closed I 



^ lorica closed f 

 beneath. 1 



E i v v. v. without horns .... Dinocharis. 



r foot styliform Monura. 



I [ lorica compressed laterally or cylindrical Colurus. 



m P smatic \ head hooded Stephanops. 



four eyes, foot furcated Squamella. 



Genus CLXVII. LEPADELLA. The scaled Rotatoria 

 are devoid of eyes, but possess a furcated foot. Several 

 rotatory muscles are seen, and foot ones in two species. 

 The jaws of the cesophagal head are single- toothed in 

 L. ovalis and emarginata ; in salpina, triple- toothed. The 



