. Bulletin - United States National Museum. Science. vou 2, pt. 2.] A TAXONOMIC STUDY OF THE SALPIDAE METCALF. 23 of the posterior face of the ganglion (ey). These have no pigment. The thin-walled ends of the rod cells lie outward in the eye and to- ward the surface of the ganglion. The dorsal pair of minute eyes lie one below the base of each limb of the horseshoe-shaped larger eye, on the dorsal surface of the ganglion (ex). The rod ends of their rod cells are turned toward the surface of the ganglion, immediately below the pigment of the larger eye. No innervation has been found for any of
. Bulletin - United States National Museum. Science. vou 2, pt. 2.] A TAXONOMIC STUDY OF THE SALPIDAE METCALF. 23 of the posterior face of the ganglion (ey). These have no pigment. The thin-walled ends of the rod cells lie outward in the eye and to- ward the surface of the ganglion. The dorsal pair of minute eyes lie one below the base of each limb of the horseshoe-shaped larger eye, on the dorsal surface of the ganglion (ex). The rod ends of their rod cells are turned toward the surface of the ganglion, immediately below the pigment of the larger eye. No innervation has been found for any of the small eyes within the ganglion of this or other species of Salpidae. In some species pigment is found associated with them. Projecting forward from the middle of the dorsal surface of the ganglion is a large horseshoe-shaped eye nearly equal in bulk to the whole ganglion (pi. 2, figs. 7-8). The middle of the curve of the. pnep FIG. 9.—CYCLOSALPA PINNATA, AGGREGATED ZOOID, A PARASAGITTAL SECTION THROUGH THE GAN. GLION, THE ACCESSORY EYES OF THE LEFT HALF OF THE GANGLION, AND THE LEFT LIMB OF THE DORSAL EYE. THE FIGURE REPRESENTS THREE SECTIONS COMBINED. X 150 DIAMETERS. horseshoe and its two ends are thick; the sides are slender. Behind and a little above the curved portion of the eye is a laterally elongated plug of optic cells, lying above the space which intervenes between the two limbs of the horseshoe. The figures show, without much description, the structure of this large eye. Figure 8 (pi. 2) is a dorsal view and figure 7 (pi. 2) a view from the right side of the eye and gan- glion. Figure 9, above, shows a parasagittal section and indicates also the position of the minute eyes in the ganglion. Figure 10, page 24, is from a transverse section of the posterior limbs of the horseshoe. Figure 1, page 11, is a diagrammatic drawing of one rod cell and a few pigment cells. One readily sees in figure 9, above, the innervation of the rod cells of the limbs of the horseshoe
Size: 2056px × 1215px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
