In the tortoise the gastrointestinal movements were observed utilizing theabdominal-window-technique. The results obtained were summarized as follows:
(1) So far as the intestine was exposed to the atmosphere both in vivo and in vitro, the intestine was motionless in most cases. On the other hand, the abdominal-window-technique proved to be very useful to observe the gastrointestinal movements.
(2) The operation was carried out under the aseptic precuation as follows: First the back of the animal was removed at its left side to make a rectangular window of 8 × 2.5-4 cm, then ovaries and fallopian tubes on the left side were removed and lastly the window thus formed was covered with a 0.2 mm thick, transparent vinyl-plate, being sutured at its border to the back. In addition, the border of the window plate was firmly sticked to the back by means of adhesives, Aron Alpha A and Araldite.
(3) a. In the region of the stomach situated just anal to the cardia contractions (stomach peristalses) recurrently started with a time interval of 21 to 32 sec, sweeping down the wall of the stomach with a velocity of 0.5 to 0.9 mm/sec, until they came to an end at the pylorus.
b. In the small intestine, there recurrently occurred contraction waves with a time interval of about 45 seconds, traveling analwards with a velocity of about 0.3mm/sec.
c. In the large intestine, there were observed two kinds of movements, i.e., antiperistalses as well as mass peristalses. Tn the former contraction waves recurrently started at the anal end (coprodaeum) of the large intestine with a time interval of 18 to 25 sec, propagating oralwards with a velocity of about 1 mm/sec, until they waned rapidly to disappear after propagating only a short distance (about 2 to 3 cm). In the latter powerful contractions occasionally started at the uppermost part of the large intestine to propagate analwards at first slowly with a velocity of about0.15 mm/sec, and then rapidly with a velocity of about 0.5 mm/sec, until they arrived at the proctodaeum to expel a fecal mass 7 to 8 mm thick and 15 mm long.

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The isolated bile duct preparations, which contain the duodenal circular muscle, and the proper bile duct muscle preparations in the dolphin (Stenella caeruleoalbus) were used and their longitudinal motilities were recorded by means of strain gauge transducer.
1. Raising the intraluminal pressure produced the augmentation of the motility of the bile duct preparation.
2. Acetylcholine and carbamylcholine caused the increase of the motility of the bile duct preparations. After atropinization the excitatory response was completely abolished.
3. Adrenaline caused the inhibitory response more predominantly than the excitatory one in the bile duct preparations, while in the proper bile duct muscle preparations it induced the excitatory response more predominantly than the inhibitory one.
Phenylephrine produced mainly the excitatory effect in both preparations, while isoprenaline did chiefly the inhibitory one.
These experimental results suggest that activation of α- and β-adrenergic receptors in the bile duct muscle causes the excitatory and inhibitory responses, respectively.
4. Transmural electric stimulation induced both excitatory and inhibitory responses in the bile duct preparation. The former response was abolished after atropinization, while the latter one was not. It may be, therefore, suggested that the excitatory response was induced by stimulation of cholinergic neurons, while the inhibitory one was produced by that of the adrenergic fibers and non-adrenergic inhibitory neurons.

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The gastro-electromyographical changes after vagotomy were studied by means of chronic insitu experiments on eighteen dogs.
Basic electric rhythms (slow spikes) were classified into normo-peristalsis and antiperistalsis. The periodical rhythm of normo-peristalsis was partly disturbed after selective vagotomy but was more regular after feeding. Normally, rate changes of normo-peristalsis show typical patterns depending on the types of meals. These distinctive features were observed more clearly in S. V. and S. P. V. dogs. The incidence of normo-peristalsis and anti-peristalsis during fasting was high in normal dogs and low in S. V. dogs by night.
A high level of anti-peristalsis occurred at the antrum in S. V. dogs. Thus, the numbers of normo-peristaltic waves reaching the antrum were decreased in S.V. dogs. After feeding, anti-peristalsis decreased in S. V. dogs but increased in normal dogs.
Anti-peristalsis tended to occur in succession with a short cycle just like extrasystole. The author noted that sometimes anti-peristalsis was propagated towards both the orad and the pylorus simultaneously.
In both S. V. and S. P. V. dogs, the denervated corpus seemed to have similar functions. On the other hand, in both the S. P. V. and normal dogs, the antrum seemed to function similarly.

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1. A study was made in vivo experiments of a contraction of stomach of the dog to stimulation of the extrinsic nerves, medulla oblongata and thoracic cord in the presence of atropine.
2. An atropine-resistant contraction of stomach was produced without accompanying any preceding relaxation of stomach motility. It seems to deny that an atropine-resistant contraction appears to be a rebound phenomenon.
3. An atropine-resistant contraction was produced in prolonged stimulation.
A delay of latency to produce a contraction of stomach was more than 27 sec and a contraction was decreased in amplitude and frequency in the presence of atropine.

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