THYKEOID GLAND OF THE TELEOSTS 



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Fig. 12. Sections through the thyreoid gland of Sarda. A, near the anterior 

 end of the gland; B, in the region of greatest extension anterior to the aortic bifur- 

 cation; C and D, close to the aortic bifurcation; E, near the second branchial 

 arteries, the region of greatest extension. 



the lateral parts increase posteriorly. Thus in the sections there 

 are three portions of thyreoid which become more and more sepa- 

 rated by the enlargement of the copula (fig. 12, D). Behind the 

 aortic bifurcation some follicles appear below the aorta; the middle 

 mass again enlarges and the three parts unite. One branch again 

 extends into the copula and soon becomes smaller, while the lateral 



