142 ANNELIDES. 



His Hypogceones have, besides, an azygous seta on the back of 

 each ring. 



The only species known is from America*. 



Messrs. Audouin and M. Edwards also distinguish the Trophonia, 

 which have four bundles of short setae on each ring, and on the an- 

 terior extremity a great number of long and brilliant setae which 

 surround the mouth f. 



NAIS, Lin. 



The Naides have an elongated body, the rings of which are less dis- 

 tinct 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 observed 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. 



Some of them have long setae J. 



And sometimes a long proboscis before . 



Or several small tentacula at the posterior extremity ||. 



Others have very short setae ^f. 



Certain Annelides, hitherto referred to the Lumbrici, which con- 

 struct tubes of clay, &c., in which they live, might be approximated 

 to this genus **. 



CLYMENA, Sav. 



The Clymense also appear to belong to this family. Their thick 

 body has but few rings, which are mostly furnished with stout setae ; 

 a little 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 ff- 



* Hypogceon Urtum, Sav., Eg., Annel., p. 104. 



f Trophoniu barbata, Aud., and Edw., Littor., de la France, Annel., pi. x, f. 

 1315. 



Nats elingws, Mull., Wurm., II ; N. littoralis, Id., Zool., Dan., Ixxx. 



Nats proboscidea, Id., Wurm., I, 1 4, of which Lamarck makes his genus 

 STYLARIA. 



tl Nats digilata, Gm., cteca, Mull., Ib., V, the genus PROTO, Oken. 



^ Nais vermicularis, Gm., Uses., Ill, xciii, 1 7; N. serpentina, Id., xciii, 

 Mull., IV, 2 4 ; Lumbricus turbifex, Gm., Bonnet., Vers d'eau douce, III, 9, 10, 

 Mull., Zool. Dan., Ixxxiv ; Lumbricus Uneatus, Mull., Wurm., Ill, 45. 



** Lumbricus tubicola, Mull., Zool. Dan., Ixxv ; Lumb. sabellaris, Ib., civ, 5. 

 M. Lamarck unites them with the Na'is tubifex, and makes it his genus TUBIFEX ; 

 it requires, however, a new examination. 



ff Clymena amphistonia, Sav., Eg., Annel., pi i, f. ; Cl. lumbricalis, Ott. Fabr., 

 Aud. and Edw., Litt., de la France, Annel., pi. x, f. 1 6 ; Cl. Ebiensis, Aud., and 

 Edw., Ib., f. 812. 



