AUTHOR'S ABSTRACT OF THIS PAPER ISSUED 

 BT THE BIBLIOGRAPHIC SERVICE, DECEMBER 27 



CONTRIBUTION TO THE MORPHOLOGIC STUDY OF 

 THE THYREOID GLAND IN EMYS EUROPAEA 



SANTE NACCARATI 



Department of Histology, Royal University, Rome 



FIVE COLORED FIGURES 



NOTES ON THE EMBRYOLOGY OF THE THYREOID 



The thyreoid, together with the thymus, the postbranchial or 

 suprapericardial bodies, the carotid gland, the thymous lobules, 

 and the parathyreoids (also called epithelial corpuscles), belongs 

 to the group of organs called branchial derivatives. 



The first embryogenetic researches on the thyreoid go back to 

 Buschke ('26), Rathke, Remak ('55), and Gotte ('67) and, with 

 many others which followed not long after, were conducted 

 almost exclusively on mammals. They served to establish 

 that the thyreoid is derived from a thickening and hollowing of 

 the ventral wall of the pharynx at the level of the second pair of 

 branchial arches. 



His ('68) established that the thyreoid is derived from two 

 equal lateral rudiments in the pharyngeal wall. 



Miiller ('71), Sessel (77), and KoUiker ('79) found that in 

 mammals the thyreoid is derived from a single medial rudiment 

 in the form of a hollow diverticulum (Miiller and Seessel) or of a 

 solid bud (Kolliker) from the ventral wall of the pharynx, with 

 which it remains in temporary connection. 



Born ('83) and Fischehs ('85) found that in the pig embryo 

 the thyreoid comes from three rudiments, originally independent, 

 a middle thyreoid rudiment arising from the ventral wall of the 

 pharynx at the level of the second pair of branchial arches, and 

 two lateral thyreoid rudiments, supposed to be formed from 

 the epithelium of the fourth entodermic branchial pouches. 



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JOURNAL OF MOBPHOLOGY. VOL. 36, NO. 2 



