82 



ALBERT KUNTZ 





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Fig. 5 Transverse section through the adrenal zone in a thirteen-day embryo 

 of Thalassochelys caretta. X 150. ad, adrenal anlagen; ao, aorta, pv, anlage of 

 prevertebral sympathetic plexus; sy, anlagen of sympathetic trunks. 



Fig. 6 Transverse section through the adrenal zone in a nineteen-day embryo 

 of Thalassochelys caretta. X 150. ad, adrenal anlagen; ao, aorta; cc, cells des- 

 tined to give rise to chromaffin substance; cc', cells of sympathetic origin among 

 cortical cells; pv, anlage of prevertebral plexus. 



Fig. 7 Transverse section through the adrenals in a twenty-five day embryo 

 of Thalassochelys caretta. X 100. ad, adrenals; ao, aorta; cc, chromaffin 

 cells; pv, anlage of prevertebral sympathetic plexus. 



Fig. 8 Section of adrenal in a thirty-six -day embryo of Thalassochelys caretta. 

 X 300. cc, chromaffin substance; co, cortical substance; vs, vascular space. 



