640 



GERARDA STIASNY-WIJNHOFF 



It is comparable with those in which the dorsal ganglia lie 

 quite outside the ventral. Both have the same length, but the 

 position of the dorsal lobe is somewhat more forward than the 



Text-fig. 13. 



ya/iy, 



Cerebral organ of Drepanophorus spectabilis after Burger 

 (6, PI. viii, fig. 23), Schema. 



Text-fig. 14. 



'-t.n. 



Transverse sections through the bram in the hinder region of the 

 ventral ganglion: a, of Siboganemertes weberi; h. of 

 Drepanophorus albolineatus of Biirger (6, PI. xvii, 

 fig. 3), Schema. The two crosses give the boundary of the 

 ganglia and the corresponding places in the two genera ; c, Dre- 

 panophorus latus, just after the origin of the lateral nerve- 

 cord (6, PI. xxiv, fig. 43). 



ventral. In Text-fig. 14, a, the ventral lobe obtained its greatest 

 diameter, as the nerve-cells of the nerve-cord are partly 

 included. The two crosses give the limit of the lobes. In 



