244 B * C - H ' HARVEY AND R. R. BENSLEY. 



Inasmuch as the results just described indicated that in no 

 part of the gland system below the foveolar level did the secretion 

 of the gastric gland cells have an acid reaction, and that the 

 secretory contents of the parietal cells were even alkaline in 

 reaction it was important to test the behavior in different states 

 of physiological activity of these glands towards solutions of 

 the dye. These experiments were performed on dogs, animals 

 being kept without food for twenty-four hours, and compared, 

 as regards the reaction with cyanamin chloride, with other 

 animals at different intervals after feeding. These experiments 

 showed that the resting gastric glands gave no reaction with 

 cyanamin, while glands taken from active stomachs fifteen or 

 more minutes after secretion gave the pronounced and char- 

 acteristic reaction described above. Accordingly, the alkaline 

 reaction of the contents of the canaliculi of the parietal cells, and 

 the non-acid reaction of the contents of the lumen of the gland 

 proper, are not the reactions of resting glands, but only of active 

 glands from a stomach which is forming an acid secretion. 



The amount of cyanamin chloride at our disposal did not permit 

 our testing its action on the stomach when injected into the living 

 animal intravenously, or by injection immediately after death 

 of solutions through the blood vessels. Naphtol blue, however, 

 apparently owes its properties in this connection to admixture 

 of cyanamin, or to synthesis of the latter during the process of 

 staining, for the reaction which it gives is exactly that of the 

 pure cyanamin solutions, and we have been able to separate from 

 the commercial zinc naphtol blue double chloride small quantities 

 of cyanamin. Naphtol blue dissolved in normal salt solution 

 injected from the aorta in a rabbit killed shortly after feeding 

 will produce this reaction in every gland of the fundus region of 

 the stomach. It is difficult, however, by this method, to secure 

 a staining of the entire gland, for reasons which a consideration 

 of the blood supply of the mucous membrane will make apparent. 

 The bases of the glands stain well, but it is difficult to secure a 

 staining of the upper portions of the glands. Preparations made 

 in this way give, however, the most remarkable demonstration 

 of the canalicular system of the glands that we have ever seen, 

 resembling except for the color a perfect silver chromate impreg- 



