Archive image from page 94 of The development of the chick. The development of the chick : an introduction to embryology . developmentofchi02lill Year: 1936 Ent'-- Fig. 38. — Transverse sections through a very short primitive streak of the chick. Incubated 17 hours; no head-process. A. Through the anterior end of the primitive streak (primitive knot). Mesodermal cells are being proliferated from the ectodermal thickening; some are scattered between the two primary germ layers. The entoderm shows no proliferation, though some mesoderm cells are adhering to it. B. Fourteen sections posterior
Archive image from page 94 of The development of the chick. The development of the chick : an introduction to embryology . developmentofchi02lill Year: 1936 Ent'-- Fig. 38. — Transverse sections through a very short primitive streak of the chick. Incubated 17 hours; no head-process. A. Through the anterior end of the primitive streak (primitive knot). Mesodermal cells are being proliferated from the ectodermal thickening; some are scattered between the two primary germ layers. The entoderm shows no proliferation, though some mesoderm cells are adhering to it. B. Fourteen sections posterior to A. (Entire length of the primitive streak is 80 sections.) The mesoblast wings are forming; the primitive groove and primitive folds are indicated. The entoderm is free from the mesoderm. Ect. Ectoderm. Ent., Entoderm. Mes., Mesoderm, pr. f., Primitive fold. pr. gr. Primitive groove, pr. kn., Primitive knot. ning to spread out laterally. The entoderm is a continuous membrane without any connection with the primitive streak, and there are no cells between ectoderm and entoderm save those derived from the primitive streak. Figs. 38 A and B show the structure of the primitive streak
Size: 2190px × 913px
Photo credit: © Actep Burstov / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: 1930, 1936, archive, book, bookauthor, bookdecade, bookpublisher, booksubject, bookyear, drawing, embryology, historical, history, illustration, image, lillie_frank_rattray_1870_1947, new_york_henry_holt, page, picture, print, reference, vintage
