The inner layer we call the entoderm, the outer the ectoderm; and the "primitive mouth" is known as the blastopore.    From Wordnik.com.  [The World's Greatest Books — Volume 15 — Science] Reference

Beneath the primordial brain an invagination of the ectoderm against the entoderm is formed, later to become the mouth.    From Wordnik.com.  [Physiology or Medicine 1935 - Presentation Speech] Reference

These three layers are called ectoderm, mesoderm, and entoderm from outside inwards respectively.    From Wordnik.com.  [Physiology or Medicine 1935 - Presentation Speech] Reference

Mesenteron: the mid-gut, stomach or chylific ventricle: the middle portion of the primitive intestinal canal, lined with entoderm.    From Wordnik.com.  [Explanation of Terms Used in Entomology] Reference

Endoderm: the inner layer of the blastoderm in the embryo, giving origin to the mid-intestine and other visceral organs: see entoderm.    From Wordnik.com.  [Explanation of Terms Used in Entomology] Reference

The mesoderm that extends ventrad from the mesentery, on each side of the entoderm just described, consists of a thick layer of compactly arranged cells.    From Wordnik.com.  [Development of the Digestive Canal of the American Alligator] Reference

The entoderm, which has the appearance of being thickened because of the fact that the notochord has not yet completely separated from it, is continuous, through the blastopore, with the ectoderm.    From Wordnik.com.  [Development of the Digestive Canal of the American Alligator] Reference

The nuclei in the dorsal and lateral regions of the entoderm are arranged in a very definite layer at the basal ends of the cells, though an occasional nucleus may be seen near the center of the layer.    From Wordnik.com.  [Development of the Digestive Canal of the American Alligator] Reference

Then along the line of invagination, i.e. the primitive orifice or blastopore, runs the outer layer of cells or ectoderm into the two invaginated layers, the mesoderm (originating from the marginal zone), and entoderm.    From Wordnik.com.  [Hans Spemann - Nobel Lecture] Reference

Later the mesoderm again penetrates between the entoderm and the ectoderm.    From Wordnik.com.  [I. Embryology. 12. The Branchial Region] Reference

—The entoderm consists at first of flattened cells, which subsequently become columnar.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

The tube is lined by entoderm from which the epithelial lining of the respiratory tract is developed.    From Wordnik.com.  [XI. Splanchnology. 1. The Respiratory Apparatus] Reference

Section I passes through the disk, in front of Hensen’s knot and shows only the ectoderm and entoderm.    From Wordnik.com.  [Illustrations. Fig. 15] Reference

The entoderm which lines these pouches grows in the form of a number of solid buds into the surrounding mesoderm.    From Wordnik.com.  [XI. Splanchnology. 2. The Digestive Apparatus] Reference

The diverticulum is lined by entoderm and covered by mesoderm, and in the latter are carried the allantoic or umbilical vessels.    From Wordnik.com.  [I. Embryology. 11. Development of the Fetal Membranes and Placenta] Reference

A third region is at the hind end of the embryo where the ectoderm and entoderm come into apposition and form the cloacal membrane.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

They are partly developed from the mesoderm of the membranous cranium, and partly from that which lies outside the entoderm of the foregut.    From Wordnik.com.  [II. Osteology. 1. Development of the Skeleton] Reference

—As already stated (page 1109), the cloacal membrane, composed of ectoderm and entoderm, originally reaches from the umbilicus to the tail.    From Wordnik.com.  [XI. Splanchnology. 3. The Urogenital Apparatus] Reference

The yolk-sac (Figs. 22 and 23) is situated on the ventral aspect of the embryo; it is lined by entoderm, outside of which is a layer of mesoderm.    From Wordnik.com.  [I. Embryology. 10. The Yolk-sac] Reference

As the mesoderm develops between the ectoderm and entoderm it is separated into lateral halves by the neural tube and notochord, presently to be described.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

On the deep surface of the inner cell-mass a layer of flattened cells, the entoderm, is differentiated and quickly assumes the form of a small sac, the yolk-sac.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

In III, IV, and V the mesoderm is seen springing from the keel-like thickening of the ectoderm, which in III and IV is observed to be continuous into the entoderm.    From Wordnik.com.  [Illustrations. Fig. 15] Reference

It lies at first between the neural tube and the entoderm of the yolk-sac, but soon becomes separated from them by the mesoderm, which grows medial-ward and surrounds it.    From Wordnik.com.  [I. Embryology. 7. The Notochord] Reference

Running through its mesoderm are the two umbilical arteries and the two umbilical veins, together with the canal of the allantois—the last being lined by entoderm (Fig. 31).    From Wordnik.com.  [I. Embryology. 11. Development of the Fetal Membranes and Placenta] Reference

The primitive streak is produced by a thickening of the axial part of the ectoderm, the cells of which multiply, grow downward, and blend with those of the subjacent entoderm (Fig. 15).    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

The blastoderm now consists of three layers, named from without inward: ectoderm, mesoderm, and entoderm; each has distinctive characteristics and gives rise to certain tissues of the body.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

The floor of this cavity is formed by the embryonic disk composed of a layer of prismatic cells, the embryonic ectoderm, derived from the inner cell-mass and lying in apposition with the entoderm.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

From the sides of the primitive streak a third layer of cells, the mesoderm, extends lateralward between the ectoderm and entoderm; the caudal end of the primitive streak forms the cloacal membrane.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

Over this area the ectoderm and entoderm come into direct contact with each other and constitute a thin membrane, the buccopharyngeal membrane, which forms a septum between the primitive mouth and pharynx.    From Wordnik.com.  [I. Embryology. 5. Segmentation of the Fertilized Ovum] Reference

Bloodvessels first make their appearance in several scattered vascular areas which are developed simultaneously between the entoderm and the mesoderm of the yolk-sac, i. e., outside the body of the embryo.    From Wordnik.com.  [V. Angiology. 3. Development of the Vascular System] Reference

The cloaca is, for a time, shut off from the anterior by a membrane, the cloacal membrane, formed by the apposition of the ectoderm and entoderm, and reaching, at first, as far forward as the future umbilicus.    From Wordnik.com.  [XI. Splanchnology. 2. The Digestive Apparatus] Reference

Hypoblast: = entoderm.    From Wordnik.com.  [Explanation of Terms Used in Entomology] Reference

The entoderm forms gut.    From Wordnik.com.  [Physiology or Medicine 1935 - Presentation Speech] Reference

Ectoderm, blue; mesoderm, red; entoderm and notochord, black.    From Wordnik.com.  [Illustrations. Fig. 29] Reference