286 
in which a primary incorporation of vertebrae has taken 
place, “wenn ich auch den bisherigen ontogenetischen 
Untersuchungen darüber keine beweisende Kraft und na- 
mentlich den gewiss recht complicirten phylogenetischen 
Process zur Genüge aufhellendes Moment zuerkennen kann’ 
(lc.p. 485 
Then, however, we cannot avoid assuming that the 
hypoglossus of Amniotes does not correspond to that of 
Elasmobranchs, the occipital nerves of the latter being sup- 
posed to have already atrophied and disappeared in Am- 
phibians. The hypoglossus of Amniotes can only correspond 
to the anterior free spinal nerves of Amphibians and Sela- 
chians and thus the conclusion is inevitable that in Am- 
niotes an assimilation of vertebrae into the cranium has 
occurred for the second time (“auximetameric neocranium’’). 
Dr. H. C. DELSMAN. 
(Wordt vervolgd). 
