88 ANATOMY OF THE CENTHAL NEETOUS SYSTEM. 



greater part becomes at once inclosed in a fascicle with several vagus roots 

 and passes toward the spinal cord. Throughout the whole course as far as 

 the first cervical nerve it is to be traced as a separate bundle. 



The Radix bulho-spinalis Vagi et Glosso-pharyngei gradually buries itself 

 just like the bulbo-spinal root of the Trigeminus: in a thin column of gray- 

 matter which lies near it throughout its whole course. That is the bulbo- 

 spinal terminal nucleus of this nerve. The fascicle is easy to find, ventral 

 from the sensory nucleus of the Vagus. 



... ■•-■■. J 



Granular layer. 

 Nucl. globos. cerebelli 



Nucl. Deiteri 

 Nucl. N. 'VIII Tub. aeusticum 



Tr. acust.-cei'ebellaria 



Nuol. N. VIII dorsal. 



Nucl. N. abducentis 



Nucl. terminal. N. glosso-phar. 



N. acusticua 



Tr. bulbo-spin. N. V. 



N. gloaso-pharyngeus 



Nucl. N. facialis 



Nucl. of the raphe 



Fig. 47. — Region of the entrance of the Glosso-pharyngeus of a young spar- 

 row, in which the development of the medullary nerve-sheaths is not yet 

 complete. 



The spinal cord offers, especially in fishes, nnmerons good examples of 

 the fact (already cited in the description of the spinal cord) that from the 

 small primitive fundaments are developed exceedingly important structures 

 according to the various development of the. peripheral organs. It is only 

 with difficulty that the mature structures can be traced to their origin. The 

 angler-fish — LopJikis piscatorius — possesses, upon its head, lateral lines and 



