ABRANCHIATA. 301 



others are deprived of them. This has caused their division into 

 two families. 



FAMILY I. 



ABRANCHIATA SETIGERA. 



This first family comprises the Lumbrici and Naides of Linnaeus. 



LuMBEicus, Lin. 

 The Earth-worms, as they are commonly called, characterized by a long-, 

 cylindrical body, divided by rug-je into a great number of rings, and by an 

 edentated mouth, necessarily required to be subdivided. 



LUMBKICUS, CuV. 



Eyes, tentacula, branchiae and cirri, all wanting. The nervous cord is no- 

 thing more than a crowded suite of numerous little ganglia. 



Every one knows the Common Earth-worm — Lumbricus terrestris, L.— 

 with a reddish body, that attains nearly a foot in length, and which is com- 

 posed of upwards of one hundred and twenty rings. Under the sixteenth 

 ring are two pores, the use of which is unknown. 



This animal traverses the soil in every direction, and swallows a quantity 

 of earth. It also eats roots, ligneous fibres, animal fi-agments, &c. 



Nais, Lin. 

 The Naides have an elongated body, the rings of which are less distinct than 

 in the Lumbrici. They inhabit holes made by them in the ooze, from which 

 one half of their body projects and is constantly in motion. Black points 

 are obser^'ed on the head of some of them, which may be taken for eyes. 

 They are small worms, whose power of reproduction is as astonishing as 

 that of the Hydrse. Several species are found in the rivers, &c. of France. 



Climena, Sav. 

 The Clymenae also appear to belong to this family. Their thick body has 

 but few rings, which are mostly furnished with stout set»; a httle higher, 

 and near the back, is a bundle of finer ones. There are neither tentacula 

 nor appendages to the head. Their posterior extremity is truncated and 

 radiated. They inhabit tubes. 



