File:Christian faith in an age of science (1903) (14590930460).jpg

Identifier: christianfaithin00rice (find matches)
Title: Christian faith in an age of science
Year: 1903 (1900s)
Authors: Rice, William North, 1845-1928
Subjects: Religion and science
Publisher: New York, A.C. Armstrong and Son
Contributing Library: Princeton Theological Seminary Library
Digitizing Sponsor: MSN

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:
from the main stem of the aorta, the cavity ofthe pharynx extends itself on each side into a seriesof pouches, which nearly meet a corresponding seriesof depressions on the sides of the neck. In fishes thesepouches open externally, the openings being the gill slitswhich are so conspicuous in the neck of a shark. Ithas been commonly asserted that such perforations areformed in the embryos of all vertebrates; but morerecent studies seem to indicate that, in the mammalianembryo, at the stage of fullest development of thepharyngeal pouches, a thin membrane separates eachpouch from the corresponding external depression. Itis, however, none the less obvious that these pouchesand the corresponding external depressions are homol-ogous with the gill pouches and gill slits of a shark. Inthe adult mammal these structures are obliterated, withthe exception of one on each side. In the case of thatone, the pharyngeal pouch becomes the Eustachiantube, the external depression becomes the external 184
Text Appearing After Image:
Fig. 11.—Three successive stages of embryos in four classes ofvertebrates. ^, shark; ^.salamander; C, chick; A man.The formation of gill slits is seen in the earliest stage of allalike; but the slits are seen to persist in the fish, and to dis-appear in the others. From Romanes Darwin and AfterDarwin. The Origin of Species auditory meatus, and the membrane between them(with some modification) becomes the tympanicmembrane. If we were converting a Roman trireme into a steam-boat, we should find it convenient to plug up most ofthe oar-holes, though it might be advantageous to keepsome of them for use as port-holes; but, if we werebuilding a steamboat de novo, it would be an absurdprocedure to bore a series of holes almost through itssides, simply that we might have the opportunity toplug them up.* The law that immature stages of higher or morespecialized organisms tend to resemble the adult formsof lower or less specialized organisms, is of very wideapplication. In many cases, however,

Note About Images