(1) When in frogs, Rana nigromaculata and Rana catesbeiana, the mucosa close to the aditus laryngis as well as to the esophageal opening was gently stroked with a piece of absorbent cotton, there occurred abrupt and powerful contractions of the abdominal muscles, being accompanied with the prolapsus of both esophagus and stomach into the mouth wide open. As regard to the gastric motility neither augmentation nor inhibition was to be seen.
The mechanism of the prolapsus may be as follows: At first the contractions of the abdominal muscles produce a sudden rise of the abdominal pressure and this then forces the stomach upwards into the esophagus, until both esophagus and stomach are turned inside out.
From the results described above, it may be concluded that in the frog the abdominal muscles play a major role in the vomiting, whereas the stomach has no active concern with it.
(2) When 0.5 ml (Rana nigromaculata) or 5 ml (Rana catesbeiana) of the tartar emetic-Ringer solution whose concentration of the emetic was 0.05 g/ml were introduced into the stomach, not only the prolapsus but also the excitation of the movements of the stomach was elicited. The latter phenomenon should be attributed to the drug action upon the neuro-muscular apparatus of the stomach, because upon the stomach of the pithed frog the drug also exerted the excitatory action similar to that observed in the intact frog.

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A 6-shaped recirculating loop and a double jejunal pouch were made in the small intestine of adult dogs for study of their functions as a substitute for stomach.Observations were performed by such methods as measurement of action potential of smooth muscle (extracellular electrode method), X-ray checks and recording of intraluminal pressure curves with an electric manometer.
The 6-shaped recirculating loop, which was 50 cm in length, had a certain capacity to accommodate the contents, without showing any significant expansion.
Concerning the action potential, there was no remarkable change in cycle of spike burst generation, and in amplitude in spike potentials, in groups of 20 cm and 50 cm loop in length. But in the group of 80 cm loop in length, the frequency of spike burst generation was decreased and some irregular patterns were observed.
Inside the double jejunal pouch of pantaloon shape, the contents stagnated temporarily but remarkable expansion of the pouch was not observed . Those changes in action potential and intraluminal pressure indicated that two canals connected in parallel maintained separate intrinsic rhythms. Action potential recorded after three months indicated that there was no remarkable change in cycle of spike burst, though some decrease in activity and desynchronization of spike discharge were observed in each side of stoma. So, it would be likely that an intrinsic property and original propagation were maintained in their portions.

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For this experiment, paraffin induced phyma, shrunk phyma and artificial intussusception were produced at the terminal ileum of infant dogs .
The development process of intestinal intussusception was traced in the dogs affected with the above types of phyma and macroscopic observation as well as record of action potential of smooth muscles, were made of the artificial intussusception to examine intestinal movements contributing to the progressive dynamics of intestinal canal intussusception. The experiment revealed the followings;
1. Intestinal intussusception failed to develop from artificial phymas on the intestinal wall. This was because the intussusception did not create a stimulating factor to influence intestinal movements .
2. Macroscopic observation of artificial intussusception revealed a characteristic increase of the retraction ring on the external canal of the intussuscepted portion, suggesting accentuation of external canal movements.
Measurement of action potential of smooth muscles disclosed almost negative potential in the internal canal, and decrease in the proximal portion of intestinal canal. On the other hand, action potential of the external canal manifested an increase for a prolonged period, which showed that the external intestinal canal was contributing greatly to the progress of the intestinal intussusception.

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The present study was made to investigate the details of defecation mechanism .The subjects studied were 14 normal adults who did not suffer from intestinal diseases and 13 patients with colonic diseases who have undergone resection of the rectosigmoid.For this purpose 16 mm X-ray cinematogram was taken on every patient using barium enema in supine posture. A photo-optical measurement was performed on these cinefilms with a film motion analyzer.
The results obtained are as follows:
1. The subjects felt the urge to defecate by giving barium into the rectal ampulla .At this time enema volume of the barium averaged 196 ml.
2. The distension of the wall of the rectal ampulla by increasing the internal pressure seems to be one of the factors giving the awareness of the need to evacuate the rectum.
3. In the left side colon and rectum, obvious movement was not observed before defecation took place. The colon and rectum went down as a whole toward the pelvic space at the time when defecation started.
When distension at the ampulla by intraabdominal pressure exceeded the tension of the anal sphincter, defecation started. At the same time obvious movement was not able to be observed on the left side colon and the rectum .
4. The transportation of feces in the left side colon was observed during defecation.At the end of defecation the rectum and left side colon returned to the resting condition similar to that before defecation started . The main function of the left side colon seems to be storage of feces.
5. Good fecal continence was noticed in the cases resected the rectum at the height more than 7 cm above the anal ring.

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