Identifier: medusaeofworld02mayo (find matches)
Title: Medusae of the world
Year: 1910 (1910s)
Authors: Mayor, Alfred Goldsborough, 1868-1922 Mayer, Alfred Goldsborough, 1868-1922
Subjects: Jellyfishes Cnidaria
Publisher: Washington, D.C., Carnegie institution of Washington
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library

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:
H. V., 1887, Studies Biol. Lab. Johns Hopkins Univ., vol.4, p. 95, plat ~3> 9figs.—Maas,i892,Zoolog. Jahrb. Anat.Abth., Bd. 5, Heft 2, p. 274.—Bigelow, H. B., 1909, Mem. Mus. Comp. Zool. at HarvardCollege, vol. 37, p. 52, plates 14, 15, and 17. Mature medusa (plate 55, fig. 1).—Bell about 7 mm. in diameter, flatter than a hemi-sphere. 8 tapering tentacles, somewhat longer than bell-radius, project from sides of bellabout midway between margin and apex; these tentacles are stiff and capable of but littlemovement and are carried bent downward in scimitar-like curves. The entodermal core ofeach tentacle consists of a row of disk-shaped, vacuolated cells. This core projects inward intothe gelatinous substance of the exumbrella, immediately above the middle of the outer edge of 462 MEDUSAE OF THE WORLD. one of the 8 radial stomach-pouches. The root of each tentacle, where it fits into thegelatinous substance of the exumbrella, is thus covered with two layers of ectoderm, one being
Text Appearing After Image:
Fio. 304.—Cunoclantha oclonaria, after Brooks, in Mem. Boston Soc. Nat. Hist., vol. 3. Showing development of actinula larva and young medusa.A, young actinula. B and C, budding actinula? giving rise to medusa-buds. Dt young medusa with only 4 tentacles. E, aboral view of young medusa. continuous with the general ectoderm covering the exumbrella and the other is continuouswith the ectoderm of the main shaft of the tentacle. The ectoderm of the shaft of each tentacle NARCOMEDUSiE—CUNOCTANTHA. 463 contains many nematocysts and also deep-lying muscle fibers. Just beneath and centrifugalto each tentacle-root is a thick pad of ectoderm-cells. This is the peronium of Haeckeland it probably serves to support the tentacle that arises immediately above it. 8 loops ofthe nerve-cord extend outward from the 8 peronia to the sense-organs upon the bell-margin.These 8 loops are put into connection one with another by means of nerve tracts that runthrough the peronia. Thus the nervous system cons

Note About Images