. Bonner zoologische Monographien. Zoology. 30 longer oviducts of the oviparous species lacking a "typical" uterus are correlated with the high number of eggs generally laid by these species as numerous eggs need a larger amount of secretions to fomi a complete set of egg jelly layers (see section 5). In the pars convoluta there can be generally distinguished three main porti- ons, an anterior, a middle and a posterior one (see Fig. 11 and Jego et al. 1986). In his preserved material von Wahlert distinguished at least two portions that differed in colour and consistency. That suggest
. Bonner zoologische Monographien. Zoology. 30 longer oviducts of the oviparous species lacking a "typical" uterus are correlated with the high number of eggs generally laid by these species as numerous eggs need a larger amount of secretions to fomi a complete set of egg jelly layers (see section 5). In the pars convoluta there can be generally distinguished three main porti- ons, an anterior, a middle and a posterior one (see Fig. 11 and Jego et al. 1986). In his preserved material von Wahlert distinguished at least two portions that differed in colour and consistency. That suggests a „tiefergehenden anatomischen und physiologischen Unterschied zv^ä- schen den beiden Abschnitten der Pars cojwoluta^' (fundamental anatomical and physiological difference between the two portions of the pars convoluta, von Wahlert 1953, p. 81). In brief, the macroscopic view shows that each of the both oviducts of the Urodela begins with the ostium and continues in a convoluted part that can be easily divi- ded in three main portions and the "uterine" portion. Degree of convolutions and their thickness are taxon-specific, but also depend on the reproductive cycle. Microscopic anatomy Light microscopy. The fully differentiated urodele oviduct is covered externally by the thin peritoneal epithelium; it is followed by a muscle layer, loose vascularized connective tissue and the oviductal lining. The muscle layer becomes thicker and may be differentiated in longitudinal and circular muscles ( Stieve 1918), particularly in the uterus of viviparous species. Also density of blood vessels in the connective tissue increases in the uterine portion ( Boisseau 1980). In the uterus of a medium sized pregnant female of Salamandra salamandra the total length of capillaries amounts to approximately 38 m (Greven & Guex 1994) (Fig. 3). The wall of the oviduct forms longitudinal folds of different length protruding in the oviductal lumen ( Stieve 1918;
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