Miscellaneous. 67 



Further, as regards the occurrence of leucotic fishes, Brandt, in 

 the memoir above cited, describes a sterlet {Acipcnser ruthcnus), 

 one foot in length, which was kept in the basin of the fountain of 

 the Winter Garden at 8t. Petersburg, and had been brought there 

 from Nischnij-jSTovgorod. With the exception of an inner silvery 

 border, the iris was destitute of black pigment, so that the eye in 

 front appeared for the most part veined with red, in consequence of 

 the vessels shining throiigh. With the exception of the very light 

 pale grey this, the ground-colour of the fish was pale brownish 

 orange, with a flesh-coloured tinge on the sides and belly, while the 

 somewhat darker dorsal surface had a yellow tinge, 



Siebold (I. c. p. 18) mentions a loach {Cohltls harhatula) of a pale 

 reddish colour and with a red pupil, which he found in the fisli- 

 market at Munich ; and in the same place ho cites Ealdner, who 

 describes a white burbot {Lota vulgaris) and a pale loach {Colitis 

 harhatula). These are the few examples of leucasthiopism that are 

 known to me. 



Consequently the occurrence of an albino eel (such as that above 

 mentioned), as well as such an abundant appearance of yellow eels 

 with black spots, have been previously unknown. — Archiv fior 

 Naturgeschiclite, Jahrg. 47 (1881), p, 136. 



On the Origin of the Central Nervous Sgstem of the Annelida. 

 By Prof. Kleinenberg. 



The author gives a summary of the results obtained by him in 

 studying the development of the Polychaeta, upon which he proposes 

 hereafter to publish a more extended memoir with figures. At 

 present he confines himself to making known the development of a 

 single species, the larva of Lopadorhijnchus., until its transformation 

 into the perfect animal. 



The most interesting point in the present communication is the 

 discovery of the circular nerve of the vibratile organ of the larva, 

 and the investigation of the development of the central nervous 

 system of the perfect animal. The author has found that during 

 the transformation of the larva into the perfect animal the circular 

 nerve disappears completely, together with the vibratile organ ; and 

 the rudiments of the typical central organs are not derived from the 

 transformation of the circular nerve, but originate from other parts 

 of the ectoderm. Consequently the nervous system of an Annelid 

 is not homologous with that of its larva. Kleinenberg thinks that 

 the larvae of the Annelida possess only the central anterior nervous 

 system of the Coelenterata, but that the perfect animals have central 

 organs proper to them ; so that " the organ of the inferior type ori- 

 ginates and functions in the larva, but is eliminated and replaced 

 by new formations in the adult animal." — Atti delta 11. Accad. dei 

 Lined, Iransunfi, vol. vi. p. 15, 1881. 



