204 



JEREMIAH S. FERGUSON 



ITBC^ 



Fig. 17. Section through the ventral margin of the thyroid gland of Squalus 

 showing peripheral venae and vasa lymphatica. 



rh- 



- -<^ol. thyr. 



, Fig. 18. Section of the thyroid gland of Carcharias showing the disintegrating 

 ^nuclei of leucocytes or red blood cells within the intrafollicular colloid. 



