. Elementary text-book of zoology. Zoology. 98 OKGANIZATION AND DEVELOPMENT OF ANIMALS IN GENEBAL. obtains in the marine Polychpeta, in which the ova and spermatozoa are developed from the epithelium of the body-cavity (mesoderm), and dehisced into the body cavity. Usually, however, special glands, the ovaries and testes, are developed, which perform no other function than that of secreting ova and spermatozoa (Echinoderms). As a rule, however, there are found associated with the male and female generative glands accessory structures and a more or less com- plicated arrangement of ducts, which
. Elementary text-book of zoology. Zoology. 98 OKGANIZATION AND DEVELOPMENT OF ANIMALS IN GENEBAL. obtains in the marine Polychpeta, in which the ova and spermatozoa are developed from the epithelium of the body-cavity (mesoderm), and dehisced into the body cavity. Usually, however, special glands, the ovaries and testes, are developed, which perform no other function than that of secreting ova and spermatozoa (Echinoderms). As a rule, however, there are found associated with the male and female generative glands accessory structures and a more or less com- plicated arrangement of ducts, which discharge definite functions in connection with the development of the generative products subse- quent to their separation from the glands, and ensure a suitable meeting between the male and female elements (fig 90). The ovaries are provided with ducts, the oviducts, which are not rarely derived a. 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 Claus, Carl, 1835-1899; Sedgwick, Adam, 1854-1913; Sinclair, F. G. (Frederick Granville), b. 1858. New York : Macmillan
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectzoology, bookyear1884
