. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. S6 MANUAL OF ZOOLOGY. As regards the reproductive process in the Corynida, the reproductive elements are developed in distinct buds or sacs,. Fig 13 —Morphology of Corynida. a Fragment of Cordylophora lacustris, slightly enlarged; b Fragment of the same considerably enlarged, showing a polypite and three gonophores in different stages of growth, the largest containing ova; c Portion oi Syttcoryne Sarsii yt\\h medusiform zooids budding from between the tentacles. which are externa
. A manual of zoology for the use of students : with a general introduction on the principles of zoology . Zoology. S6 MANUAL OF ZOOLOGY. As regards the reproductive process in the Corynida, the reproductive elements are developed in distinct buds or sacs,. Fig 13 —Morphology of Corynida. a Fragment of Cordylophora lacustris, slightly enlarged; b Fragment of the same considerably enlarged, showing a polypite and three gonophores in different stages of growth, the largest containing ova; c Portion oi Syttcoryne Sarsii yt\\h medusiform zooids budding from between the tentacles. which are external processes of the body-wall, and have been aptly termed "gonophores" by Professor Allman. Strictly speaking, Dr Allman understands by the term " gonophore " only the ultimate generative zooid, that which immediately pro- duces the generative elements. Great variations exist in the form and development of these generative buds, and an exami- nation of these leads us to some of the most singular pheno- mena in the entire animal kingdom. In some species of Hydractinia and Cory tie, the generative buds or "gonophores" exist in their simplest form—namely, as sacciform protuber- ances of the endoderm and ectoderm, enclosing a diverticulum of the somatic cavity. In this form they are attached to the " trophosome " by a short stalk, and they are termed " sporo- sacs " (fig. 14, a). They are exactly hke the buds which we have already seen to exist in the Hydra, with this difference, that they are not themselves developed into fresh polypites, but are simply receptacles in which the essential elements of generation—the ova and spermatozoa—are prepared, by the union of which the young Corynid is produced. In Cordylophora (fig. 13, ^) a further advance in structure is perceptible. The gonophore now consists of a closed sac, from the roof of which depends a hollow process or peduncle —the " manubrium"—^which gives off
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