Ohservations on Notommata Werneckii. By Prof. Balhiani. 537 



on the nervous system. On the dorsal face of the body, above the 

 pharyngeal bulb, I distinguished a pale, rounded, finely granulated 

 mass, evidently representing the central nervous organ (Fig. 2, c to) ; 

 but I could not see any of the peripheral nerves proceeding from it, 

 and which Leydig has figured.* 



The single median eye is placed, as in all Notommata, in the 

 neck, and corresponds with the posterior border of the brain 

 (Fig. 2, oe). It is composed of a small, refractive, spherical, crystalline 

 lens set in a small mass of red pigment. In some Notoinmata the 

 eye is fixed to the anterior part of a vesicle filled with opaque 

 (calcareous?) corpuscles, placed behind the cerebral mass, to which 

 it appears adherent. This is the sacculus cerehralis of Ehrenberg, 

 of quite unknown functions, and is absent in N. Werneckii. 



We must not confound with the preceding organ a small cavity 

 on the dorsal face, in front of the eye, from which it is separated by 

 the whole width of the brain (Fig. 2, c e). It seems to be bifid in 

 its anterior half, and is furnished internally with very fine vibratile 

 ciha, and contains a clear and transparent liquid. Its functions 

 appear to be as obscure as those of the sacculus cerehralis. These 

 problematical organs are frequent amongst Eotatoria, and are thought 

 by some authors to be sensitive organs on account of their more or 

 less distinct connection with the nervous centre. 



In the posterior part of the body, in front of the caudal fork, 

 are the two elongated organs general amongst Rotatoria, and which 

 Leydig, on account of their general form, calls club-shaped organs. 

 In our species they are short and fusiform, and do not reach 

 beyond the last segment of the body (Figs. 2, 8, go). Thanks to 

 the observations of Leydig, t Cohn,| Grenacher,§ and i\Iobius,|| we 

 know that they are the glandular organs producing the glutinous 

 substance which enables the animal to fasten its foot to surround- 

 ing bodies. 



III. — Reproduction. 



All the individuals which I observed were females. The 

 ovary, in the form of an elongated sac, rises in the cavity of 

 the body, beside the digestive tube, as far as the inferior part of the 

 gastric glands (Fig. 2, ov). Its posterior part, contracted into the 

 form of an oviduct (Fig. 8, od), opens, as in all Kotatoria, into 

 the cloacal canal. Its structure is very simple. In a kind of 

 granular stroma are numerous ovules, presenting the same degree 



* ' Ueber den Ban,' &c., p. 24, pi. vi. figs. 16 and 17. 



t Miiller's ' Archiv,' 1857, p. 410. 



X " Ueber die Fortpflanzung der Radertbiere," ' Zeitscbr. wiss. Zool.,' 1859, 

 vol. vii. p. 439. 



§ " Elnige Beobachtungen iiber Radertbiere," ' Zeitscbr. wiss. Zool.,' 1869, 

 vol. xix. p. 494. 



II " Ein Beitrag zur Anatomic des Brachionus plicatilis,' ' Zeitscbr. wiss. 

 Zool.,' 1874, vol. XXV. p. 111. 



