. Text-book of embryology. Embryology. Fig. 142.âDiagram illustrating the conversion of the genital fold into a closed ovary in the Teleostean fishes. in the case of the Salmon fusion of the ovarian edge with the body wall takes place anteriorly for a short distance and again in the posterior sterile region, but the greater part of the fertile region of the ovary hangs free. In such cases the eggs are shed into the splanchnocoele and pass to the exterior by genital pores (compare Cyclostomata, p. 246). Unfortunately we are still in â almost complete ignorance regard- ing the development o
. Text-book of embryology. Embryology. Fig. 142.âDiagram illustrating the conversion of the genital fold into a closed ovary in the Teleostean fishes. in the case of the Salmon fusion of the ovarian edge with the body wall takes place anteriorly for a short distance and again in the posterior sterile region, but the greater part of the fertile region of the ovary hangs free. In such cases the eggs are shed into the splanchnocoele and pass to the exterior by genital pores (compare Cyclostomata, p. 246). Unfortunately we are still in â almost complete ignorance regard- ing the development of ovary and oviducts in the Ganoids. From the little we do know it would appear that in Zepidosteus (Balfour & Parker, 1882) the ovary becomes enclosed in the same manner as in Cyprinoids (Fig. 142, B). Posteriorly it is continuous with the oviduct as in Teleosts generally. In the other Ganoids the ovary retains the form of a genital fold hanging down into the splanchno- coele while the oviduct is provided anteriorly with a coelomic funnel. The position of this funnel, far removed from the front end of the splanchnocoele, is sometimes used as an argument against the homology of this opening with the ostium of a true Mullerian duct, but such an argument carries little weight as we know from. 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 MacBride, E. W. (Ernest William), 1866-1940; Kerr, John Graham, 1869-; Heape, Walter, 1855-1929. London : Macmillan
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