LEIDY'S DESCRIPTIONS OF AMERICAN WORMS. 47 



When moderately elongated l-40th in. Found among confervse upon which it 

 feeds, in fresh water ditches in the suburbs of Philadelphia. 



Remarks. — This American species of Aeolosoma approaches the A. quaternarium 

 of Ehrenberg ; it is much smaller and has longer setse. The red spots everywhere 

 dotting the inner surface of the covering, gives it a beautiful appearance. It is 

 not so active in its movements as the preceding worms, and appears to be more 

 aquatic in its habits. 



The mouth is surrounded in the greater part of its circumference by a strong 

 muscular lower lip in the form of the letter U, with the arms presenting forward and 

 in some degree approached to each other. When closed the sides of the lower lip 

 approximate each other in such a manner that the interstice of the mouth appears as 

 an inverted T, (fig. 10.) The mouth opens into a wide but short pharynx, which 

 latter, as well as the inferior surface of the upper lip, is furnished with vibrillse. These 

 appear not to have been noticed by Ehrenberg in his observations, for he makes no 

 mention of their existence in the account of the animal. The under surface of the 

 lower lip, as well as the lining of the pharynx, is composed of hexagonal cells, 

 (fig. 11) into which the brick red globular bodies enter as nuclei. The vibrillae 

 fringe the edges of these cells, and in their movement produce a current in the water 

 towards the mouth, and are therefore an important agent in obtaining the food of the 

 animal. The intestine is simple, moderately tortuous, irregular, and capacious, 

 especially at the middle. The latter was generally found filled with green confervae. 



The brick red globules variegating the posterior part of the body, appear to be 

 coloured nuclei (fig. 12) in the muscular bands of the tegument. The median 

 vessels which convey colorless blood are very distinct. 



Enchytraeus, Henle.* — Stacheln in 4 Reihen zu 3 und 4, pfriemformig. 

 Oberlippe nicht riisselformig, wenig vortretend. Giirtel schwach abgesetzt, Vulva 

 undeutlich. Zahi der Ringe nicht liber 70. Kein Muskelmagen. Hellgelbes Blut. 

 Hqffmeister.f 



6. Enchytraeus vERMicuLARis, ifew/e.f Lumbricus? Mailer.^ — Body yellowish 

 white, fifty-six to sixty-five articulations, generative apparatus complete, perforations 

 in the eleventh articulation, girdle inconspicuous or absent. Podal setse three to five 

 in each fasciculus. Intestine capacious, no gizzard. 



Length five to eight lines, breadth i a line. Found under damp decaying logs, 

 etc., in the woods near Philadelphia. 



Remarks. — I have not access to Henle's description oi E. vermicularis, but from what 



♦ Mull. Archiv, 1837, S. 74. Arch, fiir Naturgesch. 183S, B. 2, S. 344. 

 t Arch, fur Naturgesch. 1843, B. 1, S. 186. 

 ni?id. S. 193. §Ibicl. S. 194. 



