1 1 4 SUPPLEMENT 



iijDper part of the back on each side is a series of pores very 

 symmetrically placed : it is from those orifices that the hu- 

 mour which invests the body of the lurabrici comes forth. 

 Some authors think that at the same time they are sorts of 

 stigmata for respiration. 



The general envelope of the lumbrici is eminently con- 

 tractile, in consequence of the thickness of the muscular 

 stratum, which doubles it. As for the skin itself, it presents 

 this character of irritation which is found in all the animals of 

 the class. The skin is more slender, and softer in the intervals 

 of the rings, but these latter are more inflated and more re- 

 sisting. Each of them is provided, to the right and left, 

 with a number, variable, as it would appear, according to 

 the species, of small calcareo-corneous setae, of a golden 

 yellow, disposed in pairs ; one latero-superior, and the other 

 latero-inferior, and the succession of which, on each ring, 

 forms four longitudinal series on each side of the animal, or 

 eight in all. These setas, rough and resistent, are more or 

 less short, and strongly directed backwards. This is what the 

 appendages become reduced to in this genus of animals. 

 There is, in fact, no trace of tentacular parts, not even around 

 the mouth. The intestinal canal is simple, extending fi'om 

 the mouth to the anus. The former is very small, for it is 

 pierced in the first ring, which is remarkably pointed ; but 

 as it opens a little obliquely at its inferior part, there result 

 two kinds of lips, the upper of which is oval and much longer 

 than the other, which really possesses but little sensibility. 

 There is not, at the anterior part of the canal, any buccal 

 dilatation, or teeth, or lingual enlargement. The oesophagus, 

 when arrived to about the sixteenth ring, terminates in a 

 true gizzard, almost as thick as a pea, of a fleshy and ten- " 

 dinous tissue, with fibres a little oblique. All the rest of the 

 intestine goes directly without enlargement to the anus, which 

 is pierced in the form of a longitudinal cleft in the last ring. 



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