Blue white dolphine (Stenella coaeruleo-albus) lacks the gall bladder and has the biliary duct which consists of the hepatic, common heaptic and hepato-pancreatic ducts. In the adult, the duct from the liver to the junction of the duodenum was about 5 cm long and its length in the duodenal wall was 4 to 5 cm.
It was demonstrated by maceration method and histological investigation that the muscle layers of the duct consist of four muscle layers, i. e., from the serosa inwards the longitudinal, circular, longitudinal and circular muscle layers, respectively.
The first longitudinal muscle layer originates from the duodenal circular muscle, surrounds the duct and goes up to the junction of the pancreatic duct. The second circular muscle exists in the total length of the biliary duct and connects with the duodenal circular muscle. The third longitudinal muscle is the proper biliary muscle and is thicker in the orifice of the duct, extends 1 cm out of the duodenal wall and is independent of the duodenal muscle. The fourth circular muscle layer is the submucosal muscle.
The ganglion cells are located abundantly between every muscle layers of the hepato-pancreatic and in the submucosal layer along the common hepatic and hepatic ducts.

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(1) In the colon of the fowl, Gallus gallus domesticus, there existed both Auerbach's and Meissner's plexuses, and the number of ganglion cells contained in the former was far smaller as compared with that found in mammals (guinea pig and rabbit), being estimated at 7800/cm² and 3000-4000 /cm² at the oral and middle or lower part of the colon, respectively. In addition, in the anal circumference of the chicken cloaca there were intramurally located some large ganglions containing nerve cells whose number were varied from 1500 to 2000.
(2) In the colon in situ pulsations recurrently occurred with the period ranging from 7.9 to 11.0 sec. in the anal circumference of the cloaca, traveling with the velocity ranging from 1.2 to 1.5 mm/sec. upwards the wall as shallow waves to reach the most proximal part of the colon, respectively.
(3) When the intraluminal pressure of the colon in situ was raised as high as 3 cm H₂O, the colon was at first distended for a short time (ca. 1/3 sec.), being then followed by a powerful contraction which almost simultaneously spread all over the colon; as a result a considerable amount of the cloacal content was expelled out of the anus. The contraction described above was the effect produced by an extraintestinal reflex the centrifugal pathway of which was proved to be Remak's nerve. In the fowl the movement described above might be considered to be a defecation movement.
(4) When the intraluminal pressure of the colon in vitro was raised to a height of 3 to 6 cm H₂O, at the most proximal part of the colon pulsations recurrently occurred with the period ranging from 30.0 to 33.5 sec., traveling analwards with the velocity ranging from 0.9 to 1.2 mm/sec., respectively; as the waves passed beyond the colon-cloacal junction, they rapidly waned to disappear without expelling the content out of the anus. These facts suggest that in the fowl the intramural ganglion cells of the colon have in some degree a function to regulate the strength as well as the direction of propagation of contraction waves, but they take only a minor role in the defecation.

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Eighteen dogs were used for experiments. Electodes were implanted on the stomach after selective vagotomy, selective proximal vagotomy, selective vagotomy with pyloroplasty and laparotomy (control) and electromyograms were recorded until a month after the implantation. Thirty dogs were exmained their gastric motility by means of strain gage meth od under the stimulation of various branches of vagus nerve by square pulses.
Results were:
1) Both vagotomized dogs showed remarkable increase of anti-peristaltic electrical discharges. In contrast there was no remarkable change on the normo peristaltic discharges.
2) On the selectively vagotomized dogs both peristaltic electrical discharges descreased in height contrary to normals.
3) After solid diet or hot milk, difference of patterns of normo peristaltic frequency between normal and selectively vagotomized dogs became remarkable. And its pattern in selective proximally vagotomized dogs was resemble to normals'.
4) According to results of the stimulation with block or various sections of nerves it is considered that the antral branch of vagus nerve controls also motility of lower corpus. The propagation was very quick differing from anti-peristalsis. And it was considered to be cholinergic.
5) By the stimulation of pyloric branch anti-peristalsis was scarcely occured. The pyloroplasty combined with selective vagotomy was not effective to decrease anti-peristaltic discharges after solid diet.

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1. The muscle of bile ducts does not connect with duodenal muscle and ganglion cells are observed in the submucosa and muscle layers. There is no special sphincter muscle in the orifice of the duct.
2. The bile is transproted by peristalses from hepatic side to the duodenum in vivo.
3. In the isolated bile duct (hepato-duodenal duct), raising the intraluminal pressure induced rhythmic contraction or increased spontaneous contraction.
4. Adernaline, noradrenaline and phenylephrine as well as acetylcholine increased the contraction, while isoprenaline inhibited the spontaneous contraction in number. After treatment with pindroll, adrenaline strengthened the contraction, while after treatment with phenoxybenzamine the excitatory effect responsbile to adrenaline was abolished.
5. The excitatory effect of nicotine was abolished after tetrodotoxin, but the excitatory effect induced by raising intraluminal pressure was not abolished with tetrodotoxin. However, after treatment of hexamethonium bromide, nicotine or atropine, the excitatory effect of raising intraluminal pressure was slightly reduced. It is supposed that the contraction induced by raising intraluminal pressure after treat-ment of these agents is myogenic in origin.

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