1910.] Hydrochloric Acid in the Gastric Tubules. ie 
circumscribed area in the cesophageal region, close to the opening of the 
cesophagus, and in the region of the lesser curvature adjacent to this.* In 
the guinea-pig the deposit of Prussian blue was found to occur further to 
the left of the cesophagus, z.c. further towards the fundus, than in the rabbit ; 
but in neither of these animals was it detected in the fundus region proper, 
nor in the superior half of the organ. 
In the dog the deposit was also found in the inferior half of the organ, 
and in a region slightly to the left of the cesophagus in the direction of the 
fundus, but further evidence would be required before definite statement 
could be made as to the usual situation of the deposit in this animal. 
A case of special interest, in which there was an extension of the area 
wherein the Prussian blue deposit usually occurred, was that of a rabbit 
(Rabbit 5, see Table) which had receiyed a large amount of the ammonium 
ferric citrate and potassium ferrocyanide solution in a series of five injections 
during a comparatively short space of time (50 c. cms. within 6} hours, 
injected in quantities of 10 to 11 c.cms.). The animal was killed 63 hours 
after the last injection. The injection solution had exerted a toxic influence, 
manifested by quietude and refusal of food (carrots) offered during the 
experiment. | 
The Prussian blue reaction occurred with such intensity that on the 
removal of the stomach from the body the deposit on the mucosa was visible 
through the stomach wall, appearing as a diffuse green coloration from the 
outer surface. A diagram (fig. 1) from a drawing made at the autopsy is 
given to show the area over which the colour was visible through the wall of 
the unopened stomach. 
Indications of colour similarly transmitted through the same region of the 
stomach wall were obtained in other instances in a minor degree. 
On opening the stomach the mucosa presented a remarkable appearance 
(see Plate 7, fig. 1), for in the region indicated a total area of approximately 
1i or 12 sq. ems. was covered with a thick deposit of Prussian blue of great 
intensity of colour. The deposit was greatest in amount, in the region of 
the cesophageal opening and in the adjacent region of the lesser curvature. 
The sharpness of the demarcation of the deposit in a line with the base of 
the cesophagus was a noteworthy feature. In a vertical direction the deposit 
covered about one-half of the stomach wall. In addition to the deposit in 
* The portions of the gastric mucosa designated in this communication as the 
cesophageal region and the adjacent region of the lesser curvature correspond to the 
inferior half of the median part of the greater curvature and to a portion of the inferior 
half of the smaller curvature in the arbitrary divisions of the rabbit’s stomach given by 
Langley. (J. N. Langley and H. Sewall, ‘Journ. Physiol., 1879-1880, vol. 2.) 
