Fig. 4-8. Thyroid gland of Rattus, 22 hr after an injection of 

 TSH (later stage than Fig. 4-7 d). The droplets of colloid (sc) 

 from the intrafoUicular store (above) have all moved nearer to the 

 secreting surface, which is extended towards the lumen of the 

 blood capillary (E). (From de Robertis, 1949). 



