. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 168 R. FANGE, K. SCHMIDT-NIELSEN AND H. OSAKI capillaries. These capillaries, which have frequent branchings and anastomoses, run radially out towards the surface of the lobes. In their main course the capil- laries are parallel to the tubules. Tubules and capillaries form a regular pattern in sections cut tangentially through a lobe (see Fig. 5). The tubules are polygonal in shape and the capillaries are situated at the corners of the polygons, each tubule being surrounded by 5-7 capillaries. The regularity of the arrangeme
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 168 R. FANGE, K. SCHMIDT-NIELSEN AND H. OSAKI capillaries. These capillaries, which have frequent branchings and anastomoses, run radially out towards the surface of the lobes. In their main course the capil- laries are parallel to the tubules. Tubules and capillaries form a regular pattern in sections cut tangentially through a lobe (see Fig. 5). The tubules are polygonal in shape and the capillaries are situated at the corners of the polygons, each tubule being surrounded by 5-7 capillaries. The regularity of the arrangement reminds of the rete mirabile of the fish swimbladder, or the regular arrangement of tubules and blood vessels in the medulla of the mammalian kidney. At the surface of the ARTERY. VEIN 1 central connective tissue interlobular connective tissue FIGURE 8. Diagram of a transverse section through a lobe of the salt gland. lobe the capillaries leave the tubules and pass over into a venous plexus drained by veins in the interlobular connective tissue (Fig. 8). No veins were observed within the lobes. No lymph vessels could be observed in the glands, but as they may be difficult to detect in histological sections, we hesitate to claim that there are none in the salt gland. A diagrammatic picture of the blood flow in the gland is shown in Figure 9. Innervation The nasal gland of birds has been reported to be innervated from a para- sympathetic ganglion in the anterior part of the orbit (Cords, 1904; Webb, 1957). The ganglion has connections with different cranial nerves and with the sympathetic system (Cords, 1904). The nerve supply of the salt gland in the herring gull will be described in another publication which will also deal with the physiological responses of the gland to various kinds of stimulation (Fange, Schmidt-Nielsen and Robinson, 1958). Other bird species The presence of salt glands has been demonstrated in birds of five different orders (Schmidt-Nielsen and Fange, 19
Size: 1689px × 1479px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
