. The Encyclopædia britannica; a dictionary of arts, sciences, literature and general information. remarkablydifferent in appearanceand characteristic ofdifferent groups. Infig. 4 an extremelyprimitive type is repre-sented. In mammalsMeckels tract remainsmuch more uniform; itmay be short, or in-crease enormously inlength, but in eithercase it falls into a fairlysymmetrical shape, sus-pended at the circum-ference of a nearlycircular expanse ofmesentery. Where itis short it is throwninto very simple minorloops (figs. s. 6 and 7);where it is long, theseminor loops form a con-voluted mass (figs. 8
. The Encyclopædia britannica; a dictionary of arts, sciences, literature and general information. remarkablydifferent in appearanceand characteristic ofdifferent groups. Infig. 4 an extremelyprimitive type is repre-sented. In mammalsMeckels tract remainsmuch more uniform; itmay be short, or in-crease enormously inlength, but in eithercase it falls into a fairlysymmetrical shape, sus-pended at the circum-ference of a nearlycircular expanse ofmesentery. Where itis short it is throwninto very simple minorloops (figs. s. 6 and 7);where it is long, theseminor loops form a con-voluted mass (figs. 8and 9). The third portion ofthe gut should be termed the hind-gut and lies between thecaecum or caeca and the anus, corresponding to the largeintestines, colon and rectum of human anatomy. It isformed from a much larger portion of the primitive straightgut than the duodenum and Meckels tract together, and itsproximal portion, in consequence, lies very close to the originof the duodenum. In the vast majority of birds, the hind-gutin the adult is relatively extremely short, often being only from. Fig. 7.—Intestinal Tract of Tapir. 5,cut end of duodenum; J?, cut end ofrectum; C, caecum; CL, colon.
Size: 1389px × 1799px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectencyclo, bookyear1910
