PLATE 2 



EXPLANATION OF FIGURE 



This plate consists of two reconstructions. The upper shows a left lateral 

 view of the brain and cervical cord with the nerves in situ, the aortic arch, and 

 other arteries of the left side of the head and neck. It also represents the oral, 

 nasal and pharyngeal epithelia; the left thymic and thyreoid anlagen; and illus- 

 trates in a measure the relation of the nerves and arteries to these epithelial 

 structures. The lower reconstruction shows the pancreas and spleen within the 

 mesogastrium (a portion of the stomach having been removed) ; the left genital 

 ridge, and the left meso- and metanephros with their ducts opening independently 

 into the urogenital division of the cloaca (H. E. C. S39). X 11.2 diams. 



103 



