54 R. R. BENSLEY 



EXPLANATION OF PLATE 



1 A group of follicles from the thyroid gland of the opossum, fixed in forma- 

 lin Zenker, stained with brasilin-wasserblau. X 1050. In the outer poles of the 

 cells a material differentially stained, similar to the intrafoUicular colloid. In 

 two cells droplets of colloid destined for storage. 



