File:The American journal of anatomy (1901) (14783990135).jpg

Identifier: americanjournalo06wist (find matches)
Title: The American journal of anatomy
Year: 1901 (1900s)
Authors: Wistar Institute of Anatomy and Biology Association of American Anatomists
Subjects: Anatomy Anatomy
Publisher: Baltimore, MD : (s.n.)
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
as is shown byMall, 88, in the dog, figured in his Pig. 4, Plate XX, and is surroundedon all sides by a thin layer of mesodermal tissue. On the dorso-lateral surface, above that portion which is to becomevestibular pouch and near where the endolymphatic appendage is to beseparated off from the rest of the vesicle, there is a shallow groove. Thisgroove, as seen in the sections, is cut transversely and consists of a seam,or the meeting point of the former edges of the auditory cup whoseapproximation completes the closure of the vesicle. This closure seamshows various degrees as regards the completeness of fusion, manifested George L. Streeter 143 by a difference in the thickness of the opposite edges, and the degree ofobliteration of the line of juncture. The remainder of the vesicle wallis everywhere quite uniform in appearance, consisting of 2-3 layers ofslightly elongated epithelial cells, without any apparent differentiation toindicate points of future nerve endings. 5ac. endolymph.
Text Appearing After Image:
-cochleamea.dud.ext. motor YH. Fig. 1. Profile reconstruction showing the membranous labyrinth and itsrelative size and relations to the brain and the fifth and seventh cranialnerves. Human embryo 14 mm. long, Mall Collection No. 144, magnified about8 diams. Xo epidermal stalk could be detected connecting the vesicle witli thesurface, or persisting beneath the surface epithelium, as observed in therabbit by Krause, 03, p. 88. Evidently in the human embryo such astalk must be either very temporary or else never present, as here wehave to do with a vesicle whose closure and detachment from the surfacemust be regarded as only just completed. 144 Development of Ear and VII-VIII Cranial Nerves The development of the endolymphatic appendage and its relation tothe epithelial stalk formed during the detachment of the ear vesicle fromthe epidermis has excited a considerable controversy out of which certainfacts have become definitely established. In the first place it is evident(Keibel, gg; x\

Note About Images