78 



commissura posterior, may go on the other .side to an otlier final 

 station than in the mieleus praetectalis" (op. cit., p. 262). 



In \uy opinion one of the two formations is to lie considered as 

 tlie caudal destination of this bundle, viz. tlie torns semicircniaris 

 or tlie ganglion istlimi, the first with greater prol)ability than the 

 latter. About its frontal extremity 1 cannot express an opinion for 

 the pi'esent, although the nucl. praetectalis of the other side seems 

 to be the most probable. In any case further investigations on this 

 [)oint ai'e most desirable. 



It is diffioLilt yet to say anything about the relation of the bundle 

 concerned, to the commissura praetectalis (or pars praetectalis of 

 the commissura posterior) of Edingkr. However, I have been able 

 to state with a specimen of Leuciscus rutilis that, although with no 

 other of the Cyprinoids which I examined, 1 could prove a well- 

 marked fibre connection between the commissura posterior and the 

 tr. isthmo-tectalis mihi or even the "stratum zonale" of the torus 

 semicircularis, with the said fish there existed a well characterized, 

 closed commissura bundle between the nuclei praelectales of both 

 sides. 



LITERATURE. 



ARiëNS Kappers, C. U.. Untersuchungen fiber das Gehirn von Amia calva und 



Lepidosleus osseu.«. Abhandl. d. Senckenberg. Naturforsch. Gesellsch., Bd. 30, 1907. 

 Derselbe, Die vergl. Anatomie des Nervensystems der Wirbeltiere und des Men- 



schen. 2 Bde. Haarlem 1920/ 1921. 

 ARiëNS Kappers, C. U., und Carpenter, F. W., Das Gehirn von Chimaera mon- 



strosa. b^olia neurobiol., Bd. 5, 1911. 

 Catois, E., Recherches sur riiistoiogie et I'anatomie microscopique de l'encéphale 



chez les poissons. Bull, scient. de la France et de la Belgique, tome 36. 1901. 

 Franz, V., Beitrage znr Kenntnis des Mittelhirns und Zwischenbirns der Knochen- 



fische. Folia neurobiol., Bd. 6. 1912. 

 Goldstein, K., Untersuchungen iiber das Vorderhirn und Zwischenhirn einiger 



Knochenfische usw. Arch. f. mikroskop. Anat , Bd. 66, 1905. 

 Holmgren, N., Zur Anatomie und Histologie des Vorder- und Zwischenhirns der 



Knochenfische. Acta zooi,, 1920. 

 Krause, K., Experim. Untersuchungen iiber die Sehhalmen des Goldkarpfens. 



Arch. f. mikroskop. Anat., Bd. 51, 1S98. 

 Kyozo Kudo, IJber den Torus longitudinalis der Knochenfische. Anat. Anzeiger; 



Bud. 56, 1923. 

 Mayser, p., Vergl. anat. Studiën iiber das Gehirn der Knochenfische usw. Zeitschr. 



f. wiss. Zool., Bd. 36, 1881. 



