Innervation especially sensory innervation of duodenum in white rat.

perfection of staining methods, the results were tainted with defects. In 1932, the epochal discovery of the terminal formation of the vegetative nerve fibres, that is the terminalreticulum, was made by Stohr1) and Reiser,2) after a painstaking labor. Subsequent observations by many investigators on the subject led to a remarkable illustration of the problem. On the other hand, the sensory nerves in these parts have hitherto been entirely passed over, perhaps owing to the inveterate notion that no such nerves are found in these regions. However, in the latest days, it has been ascertained that sensory nerve fibres do exist in these parts by Seto3) and Sato4) in our laboratory. In succession to the above mentioned discovery of sensory nerves, I have been able to ascertain the existence of sensory nerves in the duo denum as well as the stomach of the white rat. On the latter I have reported my findings previously.5) I will make a statement on the in nervation of duodenum of the white rat, with special emphasis of sensory nerves, hereunder. The materials of study were fixed, for a long period, in 10% neutral formol, and cut into 40ƒÊ frozen sections, which were stained by Seto's silver impregnantion. Then, the preparations stained very beautifully were subjected to minute microscovic observation.