THE FORM OF THE HUMAN STOMACH 483 



including the horse, pig, rat, rabbit and man. He did not 

 describe or label the subdivisions of the pars pylorica, which 

 however are clearly shown in his figure of the everted human 

 stomach (fig. 3). 



In connection with Home's work, the following more recent 

 physiological observations are of interest. Schutz (1885) found 

 that in the dog's stomach, contraction waves travel from the car- 

 diac end to a place about 1 cm. from the beginning of the pyloric 

 antrum (pars pylorica?), which in the isolated resting stomach 

 may be recognized by a shallow annular constriction about 2 cm. 

 behind the pylorus, and there end with a deep 'prae-antral con- 

 striction.' The second phase, which follows the first immediately, 

 concerns the antrum only. The motions of the two parts may 

 take place independently of one another. Moritz (1895) deter- 

 mined the pressure within the two parts of the stomach, and stated 

 that the difference between them was greater than would be 

 inferred from merely observing their motions. Cannon (1898) 

 found that the stomach of the cat, as shown by X-ray examina- 

 tions, is composed of two physiologically distinct parts — a 

 'busy antrum' and a cardiac reservoir. In 1911 he states that 

 during normal digestion "slight constrictions appear near the 

 middle of the body of the stomach, and pressing deeper into the 

 greater curvature, course towards the pyloric end. When a wave 

 sweeps round the bend into the vestibule, the indentation made by 

 it increases." He adds that when vomiting occurs, a strong con- 

 traction at the angular incisure completely divides the gastric 

 cavity into two parts. Thus the observations of Home have been 

 amply confirmed and extended. Other X-ray observers, however, 

 have considered that the antrum, or pars pylorica, of anatomists 

 is merely the part of the stomach marked off by a passing peri- 

 staltic wave (Hertz; Kaestle, Rieder and Rosenthal; Barclay). In 

 this they follow Sappey (1874), who was of the opinion that 

 Home's subdivision of the stomach was based on fortuitous mus- 

 cular contractions. This will be disproved by showing that the 

 two divisions of the stomach are well marked in embryos in 

 which the muscle-layers are still scarcely differentiated. 



