40 R. R. BENSLEY 



earlier phases of pilocarpinisation, the appearance of clear drop- 

 lets in the cytoplasm, which collected at the free pole of the 

 cell, to be extruded in the form of small droplets into the cavity 

 of the vesicle. These, therefore, he regarded as the antece- 

 dents of the clear vacuoles of the margin of the colloid and on 

 account of their lack of affinity for dyes, designated chromo- 

 phobe secretion. A little later round, stainable droplets made 

 their appearance in the free pole of the cell, which likewise mi- 

 grated to the free border to be extruded into the lumen, consti- 

 tuting thus the chromophile secretion. He regarded the colloid 

 cells of Langendorff as cells destined to degenerate. Thus, 

 Anderson rejected the mode of secretion favored by Langendorff, 

 and introduced the conception of a polyvalent secretion. His re- 

 sults, in general, are in more accord with those of Biondi than 

 with those of Langendorff. 



Hiirthle ('94) in the same year studied the effects of reduc- 

 tion of thyroid tissue, and of bile retention, on the secretory proc- 

 esses of the gland. He found, as a result of each of these con- 

 ditions, a great increase in the number of cells containing colloid 

 spherules, wiiich he therefore interpreted as an evidence of accel- 

 erated activity of the gland. On the other hand he recognized the 

 occurrence of the Langendorff colloid cells to which he also 

 ascribed secretory significance, and which he considered capable 

 of transformation into principal cells. 



Galeotti ('96) studied the thyroid glands of the turtle Emys 

 europaea, under normal conditions, and after the injection of 

 various products of metabolism. He described two sorts of secre- 

 tion antecedents: fuchsinophile granules of nuclear origin, pre- 

 viously undescribed, and droplets of colloid like those described 

 by Biondi, Anderson, and Hiirthle. These two secretion ante- 

 cedents varied independently of one another under the experi- 

 mental conditions employed. 



Following Galeotti a number of different observers using his 

 methods studied the thyroid gland under different experimental 

 and pathological conditions, confirming his results as to the 

 double character of the thyroid secretion and the independent 

 variation of the two sorts of secretion. Among these may be 



