Brosian und RiBTz, Verdauungsrohr. 



515 



,,cinL' äußere Längs-, mittlere Kreis- und innere Längsfasersehicht. Die Subniiicosa ist seliwacli entwickelt, die iluseu- 

 laris nuicosae deutlich; letztere sendet schwache Fortsätze in die Mueosa hinein." 



,,Die Oberfläche der Schleimhaut trägt feine Zotten; ihre Drüsen, sind im linken Sack und dem blinden Ende" f= der 

 Umbiegungsstelle) ,,Belegzelldriisen, mit sehr reichlichen Belegzellen." 



„Im Pylorusteil des Magens sind die Zotten größer und stehen dichter. Die engen Drüsen rollen sich am Grunde 

 sehr stark auf. Sie haben hohe, schmale Zylinderzellen, mit peripher gestellten Kernen" (zit. nach Oppel. 1896). 



Nach PiLLiET (1894) zeigen die Magendrüsen bei Phoca vitulina 



,,vün der Cardia bis zur Pylorusregion dieselben Charaktere. Sie sind kurz, enthalten Haupt- und Belegzellen in der 

 gewöhnlichen Verteilung, Hauptzellen im Grunde und in der Achse der Drüse, Belcgzellen randständig und im Drüsenhals. 

 Die Drüsenschläuche stehen in Gruppen von 10— l.ö. Die einzelnen Gruppen sind voneinander durch fibrilläres Bindegewebe 

 getrennt." 



Bei Otaria jubata sind nach demselben Autor die Pepsindrüsen 



.,viel länger als beim Hunde. Sie bilden Grup])en, deren tiefes Ende entwickelt, angeschwollen und beinahe acinös 

 ist. Alle diese Gruppen sind voneinander durch reichliche Bindegewebszüge getrennt. — Die Pylorusdrüsen sind wenig ver- 

 zweigt" (zit. nach OPFicr., 1896). 



Hepburn (1896) beschreibt mit folgenden Worten den Digestionskanal usw. bei Halichoerus 

 grypus: 



„The Oesophagus was a powerful nuiscular tube, lined by a mucous membrane thrown into longitudinal rugae. When 

 stretched, the mucous membrane presented a uniform surface, studded with numcrous line granulär points, as if dusted with 

 sand. Close to its junction with the stomach it measiired 2'/iinehes in diameter, and very readily admitted my hand and 

 forearni." 



„The stomach, emptied of its contents, and lying flaccid on a table, presented a lesser and a greater curvature, to 

 cach of which there was attached a corresponding Omentum. Close to the pylorlc end of the lesser curvature there was a 

 slight diverticulum or sacculation projecting in the direction of the liver. 



The oesophageal end of the stomach presented a cardiac enlargement on its greater curvature, but it did not rise 

 above the level of the cardiac orifice. The most pronounced bulging on the greater curvature was seen in its pyloric half. 

 The external diameter at the cardiac orifice was similar to the width of the Oesophagus, viz., 2t2inches; externally the 

 ])ylorus was indicated by a strong resistant ring, almost cartilaginous in its consistence. The greatest transverse diameter of 

 the stomach in its enipty State, from the pyloric orifice to the great curvature, was 12 inches; the greatest length from the 

 oesophageal orifice to the greater curvature at a point in the ])yloric half of the great cnrve was 14 inches. 



There was an abrupt, distinct, but not absolutely straight line of deniarcation between the gastric and oesophageal 

 mucous membranes. In the stomach, the mucous membrane was darker, thicker, and more s])ongy than in the Oesophagus; 

 and when shghtly stretched, mimerous pit-hke openings becanie visible. 



I passed my hand and forearm through the Oesophagus into the inferior of the stomach, and onwards towards the 

 pylorus. At a point on the lesser curvature, 4 inches from the pylorus something of the nature of a curtain or partition 

 projected towards the inferior of the stomach from the lesser cnrve. As a consequence of this arrangement, the cavity of 

 the stomach formed a recess on the pyloric aspect of this curtain. By changing the position of my hand and passing it 

 along the great curvature, I found no obstade to its progress as far as the pylorus, through which it was impossible to 

 force niy finger into the duodenum, because the passage was blocked by a rounded, valve-Uke, and fairly rigid päd, pro- 

 jecting from the inferior or hinder aspect of the pylorus. However, by reversing the position of my hand and applying it 

 to the lesser curvature, a passage into the duodenum was easily efl'ected, although in this position there was also a smaller 

 projecting valve-like päd. The pyloric orifice would only transmit my niiddle finger, which implies a diameter of shghtly 

 more than half an inch. 



When the stomach was inflatcd to a moderate size, a very acute flexure was seen in the region of the lesser cnrve, 

 nearer to the pylorus than to the Oesophagus. The sides of this flexure were maintained in close apposition by the gastro- 

 hepatic Omentum, and it was at once evident that this feature of the stomach wall accounted for the projecting curtain 

 found on the internal aspect. 



In its partially distended condition the stomach somewhat resembled an invcrted egg-shaped retort. — the Oesophagus 

 being attached to the larger end, the abrupt flexure representing the neck, and the pyloric dilatation Ihc wide outlet, from 

 which the duodenum was continued. No doubt the acute flexure in the stomach wall is a mechanical arrangement for securing 

 an eftective circulation of its Contents, whereliy undigested masses would be directed against the greater curvature, while 

 their escape through the pylorus would be easily prevented by its strong valvulär pads. Certainly, although large masses 



