Brachionaea.'] THE INFUSORIA. 409 



FAMILY XXX. BRACHIONAEA. 



The concluding family of the Rotatoria, Brachionaea, is 

 distinguished by its members being provided with two 

 rotatory, organs, and in possessing a lorica. 



The lorica is a testula, and not a scutellum. The ro- 

 tatory apparatus is often apparently composed ofive parts, 

 three central and two lateral. The latter alone constitute 

 the rotatory organs, the others are only ciliated frontal 

 portions, which, during the vibration of the rotatory 

 organs, remain stiffly extended as feelers. Some (perhaps 

 all) have two setae at the rotatory apparatus, as in Syn- 

 chaeta. The genera Noteus and Brachionus have a forked 

 foot, Anuraea is destitute of foot, and Pterodina has a 

 sucking disc at the end of the foot, but no toes. All the 

 genera have jaws, with teeth, attached to an cesophagal 

 head, having four muscles. In Pterodina the jaws are 

 partly two-toothed and row-toothed (zygogomphia locho- 

 gomphia), in the other genera they are many- toothed 

 (polygomphia). In Noteus and Pterodina the alimentary 

 canal is constricted, forming stomachs (gasterodela) ; in 

 the rest it is partly simple (coelogastrica), partly with sto- 

 machs. Biliary glands have been observed in all the 

 genera, as also an ovarium, male glands, and contractile 

 vesicle. Many species of Anuraea, Brachionus, and Noteus, 

 carry their eggs attached to them, after expulsion. In all 

 the genera, except Pterodina, internal tremulous gill-like 

 organs, attached to the male glands, have been observed, 

 and respiratory tubes exist in some species of the genera 



