Cites Plate XII, Journal of Physiology 1 (4-5) (1878). Figs. 1-10 from H. Sewall, 'The Development and Regeneration of the Gastric Glandular Epithelium during Foetal Life and after Birth'.
Description:

Explanation of Plate XII:

'Fig. 1. Intestine, sheep embryo 11/12 inch long. Transverse section. x 380 diameters.

Fig. 2. Stomach, sheep. embryo. 5/6 inch long. a, cells of hypoblast; b, cells of mesoderm. x 380 diameters.

Fig. 3. Flap and gland processes from sheep embryo 4 1/2 inches long. a, gland processes; b, mesoderm; c, developing muscle fibres. x 220 diameters.

Fig. 4. A single gland process from the same, more magnified. a, flattened layer of mesoderm cells. x 380 diameters.

Fig. 5. Sheep's stomach near cardia. Embryo 8 inches. a, gland processes; b, ovoid cells, somewhat too sharply defined; c, doubtful forms; d, central cells; f, embryonic cells; g, blood-vessel. x 380 diameters.'

Fig. 6. Section from pyloric part of same. a, embryonic cell; b, ovoid cells. x 380 diameters.

Fig. 7. Stomach (cat) near cardia. Shews gradations between mesodermic corpuscle and ovoid cell, a a; ovoid cell in mesoderm, b; with double nucleus, c; intermediate forms, d; gland without ovoid cells, f. x 380 diameters.

Fig. 8. Pylorus ([?]) from fasting cat after stimulation. a, ovoid cell.

Fig. 9. Surface of mucous membrane from fasting stimulated cat. a, epithelium; b, ovoid cells.

Fig. 10. Vestibule of gland from cat as above (osmic acid). a, epithelium; b, ovoid cell; c, transformation form.'  (333-334)

 

Figs. 1-4 in text:

'Where the epithelium is still arranged in a single layer the nucleus is situate in the centre of the cell, and the latter stains uniformly throughout (Fig. 1). Where, on the other hand, the cells lie in more than one layer, where in fact active cell-multiplication is taking place, the nucleus lies nearer that end of each cell which is turned away from the mesoblast, and this end of the cell or the nucleus itself is all that picks up the aniline blue (Fig. 2, a; also Figs. 3 and 4).' (323)

 

Fig. 1 in text:

'Sections taken from different parts of the alimentary canal of a lamb embryo, five-sixths of an inch in length, shew local differences in the lining epithelium. In the intestine it still consists of a single layer of large cells (Pl. XII. Fig. 1), while in the stomach and oesophagus the cells are so closely crowded that many are pushed away to a greater or less extent from the basement membrane, thus giving the epithelium the appearance of being composed of several layers.' (322-323)

 

Figs. 3-4 in text:

'Synchronous multiplication of hypoblast cells and of supporting mesoblastic corpuscles along definite intersecting lines is the first evidence of glandular formation (Fig. 3, a). Projections, which may be called 'gland processes' are thus formed; as seen in section they present a slender central mesoblastic core, from which branches penetrate between the epithelial cells covering it; Fig. 4 represents one of these processes more magnified.' (323)

 

Fig. 3 in text:

'The first protrusions of the mucous membrane are few in number, and as seen in cross section, contain a relatively broad core of mesoblast; they become the large permanent flaps of the mucous membrane of the adult stomach, and probably the rugre of other stomachs. They are seen in the section depicted in Fig. 3.' (323)

 

Fig. 4 in text:

'Immediately beneath the epithelium is a well-marked layer of mesoblast cells, flattened parallel to the surface and forming a very distinct basement membrane (Fitg. 4, a).'

 

Fig. 5 in text:

'Keeping pace with the superficial growth of the stomach-wall, new protrusions of the mucous membrane appear budding out either from the sides of those already formed or from the hollows between them (Fig. 5). This mtiltiplication of outgrowths goes on, making the spaces between the intersecting ridges smaller and smaller, until they are finally reduced to minute canals, which become the lumens of the glands. It may be readily understood from Fig. 5, a, how several glands may come to open into a single vestibule by the formation of new outgrowths between two which have already attained a considerable size, the new outgrowths not growing out as far as the original ones, and so leaving a small pit which becomes the common vestibule. In a sheep's embryo about 16 inches long the glandular formation seems to be completed. Blood-vessels appear early in the mesoblastic cores of the gland processes, as extensions from vascular areas lower down (Fig. 5, g). I have first found vessels containing red corpuscles in the gland processes of an embryo 6 1/2 inches in length.' (324)

'In an embryo about 5 1/2 inches long one finds one or more cells at the bottom of a gland to have taken on new characters; they are larger, more oval, stain better, and are more granular than the 'embryonic' gland cells; and are to be regarded as the first formed 'ovoid' cells, although they differ somewhat from the fully formed 'ovoid' cell of the adult. These cells are sometimes enclosed in a close network of processes from mesodermic cells, in other cases not. Fig. 5, b, shews 'ovoid' cells, (a little too sharply defined,) from an embryo eight inches long. The shape of these cells is subject to much more variation than that of the corresponding cell in the adult, and in various specimens gradations in every dharacter may be found between them and the undifferentiated embryonic gland cells, such as is represented at c in the same figure.' (325)

'The central cells (Hauptzellen) are first differentiated so as to be definitely recognisable as such in sheep embryos about 5 1/2 inches long... They are formed, I believe, by a differentiation of the embryonic cells, accompanied by division. At d in Fig. 5, a series of developing central cells is depicted.' (326)

 

Fig. 6 in text:

'A wholly unexpected phenomenon was the appearance of ovoid cells in the pyloric region of the embryo stomach... Fig. 6 shews ovoid cells (b) from the pyloric region of the stomach of an embryo 8 inches in length. They appear earlier in the pyloric region than elsewhere, in accordance with the general developmental precocity of that part.' (325-326)

 

Figs. 7 and 10 in text:

'In Fig. 7, at d, forms are seen combining the characters of both 'ovoid' and central cells; in Fig. 10, at c, is an appearance as if division had just taken place.' (331)

 

Fig. 7 in text:

'The sections from non-pyloric parts of the stomachs of animals so treated shewed glands of various appearances, which may however be arranged in three groups. A few were quite free from ovoid cells, and were larger and thicker than the rest, the central cells filling them being great and clear like typical hungering cells. They resembled very closely the cells from the stomach of the lamb above mentioned. More numerous were glands also devoid of ovoid cells, but thinner than the above; their cells being smaller, more shrunken, and staining more deeply than ordinary central cells (Fig. 7).' (330)

'If the central cells do in this way disappear in the course of normal secretion, there must be some means for their replacement, and sections .from the above stomachs seem to indicate that they take their origin from the ovoid cells, usually by division, perhaps sometimes by direct metamorphosis. Signs of fission among the ovoid cells are numerous. In most of the stomachs experimented upon, many of them are unusually large, and commonly contain two, sometimes three nuclei, these appearances being most common at the deeper parts of the glands (Fig. 7, c).' (331)

'The corpuscles in the mesoderm beneath the mucous membrane of the stomach are commonly much like ordinary connective-tissue corpuscles: they are more or less branched, and radiate or triangular in optical section. Sections from the stimulated starving stomach shewed in addition undoubted 'ovoid' cells in considerable numbers in this mesoderm and entirely outside the glands. This is most marked in the deeper parts of the mucous membrane where the mesoderma is thickest, as at b, Fig. 7. These cells may abut directly upon the glands, or be isolated from them at different distances in the mesoderm: many of them are of the common 'ovoid' cell shape, but are larger, stain less deeply, and are not so sharply defined. Between such cells and the typical mesoderm cell may be found all intermediate forms, some of which may be seen at a in Fig. 7.' (332)