. Text book of vertebrate zoology. Vertebrates; Anatomy, Comparative. UROGENITAL ORGANS. 123 Ao last open into the collecting tubules; but it is important to note that at no time are nephrostomata developed in connec- tion with them, and the body cav- ity is without communication with this nephridial system. While this process is going on the whole met- anephros pushes farther forward, dorsal to the pronephric duct, the ureter increasing correspondingly in length. In the subsequent his- tory the kidney becomes strongly lobulated, the lobes corresponding to the groups of collecting tubules of w
. Text book of vertebrate zoology. Vertebrates; Anatomy, Comparative. UROGENITAL ORGANS. 123 Ao last open into the collecting tubules; but it is important to note that at no time are nephrostomata developed in connec- tion with them, and the body cav- ity is without communication with this nephridial system. While this process is going on the whole met- anephros pushes farther forward, dorsal to the pronephric duct, the ureter increasing correspondingly in length. In the subsequent his- tory the kidney becomes strongly lobulated, the lobes corresponding to the groups of collecting tubules of which it is composed. This lob- ular appearance is retained through- out life in the sauropsida, but is subsequently lost in all mammals except the whales and some car- nivores. The kidney never extends through as many segments as does the mesonephros, but forms a relatively smaller and more com- pact body lying within or a little in front of the pelvic region. In the mammals the anterior end of the ureter becomes widened out, inside of the mass of the kidney, into a considerable chamber, the pelvis of the kidney, into which the collecting tubules empty, the openings of these being placed on one or more papillae, which extend into the pelvis renalis, partially dividing it into smaller chambers or calyces. The ureter does not long retain its primary connection with the distal end of the pronephric duct, but acquires its own open-. FlG. 131. Urogenital system of male heron (^Ardea')^ from Wiedersheim. Ao, aorta; BF, bursa Fabricii, opening at BF' into the cloaca, Cc; Ep, epididymis; Ho, testes; A^, kidney; Sr, opening of ureter; V, furrows for veins on ventral surface of kidney ; Vd, vasa deferentia; Vd', their opening into Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Kingsley, J. S. (John Sterling)
Size: 972px × 2572px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyorkhholtandcom
