The development of the intramural plexuses in the tortoise, Geoclemys reevesii was inferior to that observed in the fowl: the meshes of both Auerbach's and Meissner's plexuses were coarser, and consisted of less number of nerve fibers. Occasionally, a small ganglion was seen at the crossing points of the meshes. The average number of nerve cells contained in the ganglion was estimated to be 1500/cm², being about half as much as that estimated in the fowl.
When the mucosa of a colon in vitro was stimulated mechanically by stroking or chemically with 1/10 N HCl, the excitability of the colonic muscle was raised at the region oral to the stimulated spot, but lowered at the region anal to it. These effects were abolished by applying a ganglion-blocking agent, hexamethonium (10^-6 g/ml), to the mucosa.
When the intraluminal pressure of a colon in vitro was raised from 0 to 3-12 cm H₂O, the colon was distended at first but soon contracted powerfully. The contraction became extremely reduced or was abolished when hexamethonium (3.5×10^-7-1×10^-5 g/ml) was added to the saline solution in which the colon was immersed.
The results indicate that the intramural ganglion cells serve as the center of the intrinsic mucosal reflex.

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Twenty eight adult dogs fasted over night were used under Nembutal anesthesia. The influences of distension of the pouch which was made on gatric corpus on the motility of gastric pyloric antrum were investigated. The following results were obtained.
1) Any changes were not observed on the motility on gastric pyloric antrum by distension of gastric corpus pouch by a pressure of 20mmHg, but a stepwise elevation of the lumen pressure of the pouch from 50mmHg to 100mmHg elicited a remarkable relaxation of the tone and inhibition of motility of the pyloric antrum. These inhibitory responses were not abolished by the bilateral cervical vagotomy or by the bilateral splanchnicotomy respectively, but these inhibitory reflexes were disappeared completely after the transection of both extrinsic nerves.
2) The inhibition of motility of gastric pyloric antrum were also elicited by the electric stimulation of the central cut end of vagal branch or of splanchnic branch which innervated the gastric corpus respectively.
3) It may be concluded that the reflex pathways of the gastric corpus-pyloric antrum inhibitory reflexes involve not only in vagus nerves but also in splanchnic n erves.

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The present study was undertaken to elucidate the mechanism of bile excretion of the choledochoduodenal junction (ch-d junction) in rabbits, especially regarding it's structural and physiological independence from the duodenum.
For this purpose muscular anatomy of the ch-d junction and relationship between the electromygoraphic spike potential of this juncture and the intracholedochal pressure were investigated.
The results obtained were as follows.
1. There were demonstrated proper circular muscle and proper oblique muscle in the ch-d junction, which appeared independent from the duodenal muscle. There existed a muscular sphincter at the terminus of the common bile duct, but it's muscle fibers did not appear continuous with the duodenal muscle fibers.
2. The rhythmical changing curve of the intracholedochal pressure was parallel with appearance of the spike potential but had absolutely no correlation with the duodenal one.
3. The attitudes of the ch-d junction and the duodenum to the neural control were compared.
The spike generation by Neostigmin methylsulfate was equally observed in the ch-d jundtion and the duodenum and the spike inhibition by Hyoscin-Nbutylbromide was also equally observed in both of them, suggesting their innervation was probably common.

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