32 GRAY SUBSTANCE OF THE MEDULLA OBLONGATA 



CHAPTER VII. 



THE OLIVAEY BODIES IN MAN. 



The resemblance between the convoluted folds of the corpora olivaria and the 

 corpus dentatum of the cerebellum, could hardly fail to attract the attention of many 

 anatomists. This resemblance, pointed out by Reil,' Prochaska,^ and Gall,^ the 

 latter, however, seeming to have overlooked the convoluted structure, has been very 

 plainly sho^vn by Rolando,* who makes the following statement. " II residte de 

 mes observations, qu'il n'existe presqu' aucime diversite, relativement a la structure, 

 entre les eminences olivaires et les corps denteles du cervelet. En effet, si on suit 

 les coupes qu'ils offrent tant les rms que les autres, il est facile de se convaincre 

 que la lame jaunatre et dentel^e est disposee autour du noyau, de maniere qu'il 

 en resulte une bourse aplatie, dont le col ouvert et un pen retreci est tourne vers 

 la ligne m^diane et en arriere, s'il est question des eminences olivaires ; tandis que 

 si on parle des corps denteles du cervelet, la dite lame jaunatre est plus plissee, et 

 forme une bourse plus longue et presque ronde, dont le col, plus ouvert et plus large, 

 serait retourne en avant et vers le 4° ventricule." 



The resemblance pointed out above, and the probability that the same general 

 plan exists in aU cases where this pecidiar convoluted structure is found, at once 

 invest the study of the minute anatomy of the olivary bodies with very great 

 interest, from the light thus likely to be throAvn on the analogous structure of the 

 hemispheres of the cerebrum and cerebellum. 



The external and internal form and relations of the olivaries, as seen in transverse 

 sections, have been well described by several observers, among whom Clarke' certainly 

 deserves first mention, both for the extreme accuracy and detail of his descriptions. 

 The subject is by no means an easy one, but after going over the whole ground very 

 carefuUy, and studying very many ditferent preparations, I find that my o^vn obser- 

 vations are entirely in accordance with his in every hnportant particidar. 



As pointed out by Clarke, the olivary column is developed amongst the network 

 into which the anterior cornu is resolved. This is evident by reference to Plate 

 XIV, Fig. 18", where the origin of the olivary bodies is seen just behind the pyra- 

 mid, and close to the course of the hypoglossal roots, as an elongated, somewhat 

 rounded collection of cells (0), scattered at first among the arciform fibres with 



' Arcliiv fiir die Pliysiologie, IX, 490. ° De Structura Nervorum. 



' Gall et Spurzheim, Systeme, 198. 



* Recherches anatomiques. Magendie, Journal de Physiol. lY, 336. 



* Philos. Transactions, 1858. 



