A CONTEIBUTION TO THE MOEPHOLOGY OF THE 

 MEDULLA OBLONGATA OF THE EABBIT. 



be 



interesting if their 



We owe a large proportion of our knowledge relating 

 to the development of the human spinal cord and medulla 

 oblongata to the researches of His and Cajol. Most of these 

 were made on the human embryo. 



It seemed to me that it would 

 results could be verified in the rabbit. 

 To my surprise, I found that the 

 development of the medulla of the 

 rabbit differed from the human in 

 several respects. Before describing 

 these differences, it might be well 

 to recapitulate briefly some of the 

 salient points in the development of 

 the human medulla. 



At an early stage in the devel- 

 opment of the human spinal cord, its 

 central canal might be diagrammati- 

 cally described as being somewhat 

 diamond-shaped. (Fig. 1.) 



Minot has proposed to designate 

 the different divisions of its wall 

 the zones of His. He divides 



as 



them into two dorsal (Fliigelplatte) 

 and. two ventral zones (Grundplatte), 

 a roof (Deckplatte) and floor plate (Bodenplatte). 



(Minot, 846.) Diagram- 

 matic section of the embry- 

 onic spinal cord. dpl^ 

 deck-plate. D, dorsal zone. 

 ovJ, oval bundle. DR^ 

 dorsal root. Rsch, Rand- 

 schleier. F, ventral zone. 

 N, neuroblasts. Fi?, ven- 

 tral root. i, bodenplatte. 

 (7, central canal. Ep^ epen- 

 dymal layer. 



