112 SUPPLEMENT 



nothing but simple and fleshy filaments, similar to those 

 which are attached to the rings, and only a little larger ; their 

 oesophagus can re-enter and come out so as to represent a 

 species of proboscis. When it is altogether elongated exter- 

 nally, the aperture of the gizzard presents itself, and with it 

 four small teeth that are there attached, two above and two 

 below. This gizzard is fleshy, and very strong ,: the intes- 

 tinal canal is straight, and gives out on each side a multitude 

 of ccEca which terminate sometimes by a simple dilatation, 

 sometimes by some ramifications. 



The blood vessels of the aphrodites are a little smaller in 

 proportion than those of the nereides and the arenicolae ; 

 nevertheless, it is easy to perceive them, and also to demon- 

 strate that they are filled with a red fluid. Their nervous 

 system is very apparent, and consists in a medullary cordon, 

 which predominates through the whole length of the belly, 

 and is swelled into as many ganglia as there are segments in 

 the body. 



It is said that the sexes are separated in the aphrodites, and 

 that they are oviparous. In certain seasons the body of the 

 female is found full of eggs, which swim in a liquid, and that 

 of the males full of milt ; but no internal organs have been 

 found destined to pi'oduce them, nor external apertures to 

 evacuate them. 



We shall now proceed to the third and last order — 

 Abranchia. 



The genus LuMBRicus was indicated originally by the au- 

 thors of antiquity, and admitted successively, under the same 

 denomination, by all the modern zoologists, except by M. Sa- 

 vigny. Linnaeus, Gmelin, and his followers, who are very nume- 

 rous, place this genus in the division of external worms. M. 

 Cuvier at first imitated Linnaeus ; but he gave to the division 

 of the worms in which he placed the lumbrici, the name of red- 



