ANATOMY OF VERTEBRATES. 



consist of delicate folds of membrane, inclosing stroma studded 

 with ovisacs, of two grades of size, the larger with ova for the 

 present season, the smaller for the following one. In a Siren 

 with enlarged ovaries I observed them bearing impressions of 

 the intestinal convolutions. The oviducts, ib. i, are external to 

 the ovaria, and are attached to the sides of the spine, each by a 

 broad duplicature of peritoneum. They commence anteriorly by a 

 simple slit-like aperture, with entire borders, h, are attenuated at 

 their commencement, and soon begin to be disposed in short parallel 

 transverse folds, in the Axolotl about twelve, in the Siren twenty, 

 in number, which gradually diminish near the cloaca, where the 

 oviducts open behind the rectum upon small prominences. Above 

 the kidneys, g, a linear tract, k, indicates the remnant of the 

 Wolffian body. 



The foregoing type of female organs is closely followed in 

 all the perennibranchiate Batrachia. In the Newt the ovaries, 

 as they expand, assume a lobulated exterior and greater relative 

 breadth, especially at their hinder end, than in the Axolotl. 

 Each oviduct begins by a simple slit-shaped aperture, between 

 the pericardium and liver, and passes backward in a wavy course, 

 which becomes irregular as it approaches the kidneys : here the 

 oviducts diverge from each other, then approximate at the medial 

 line, and again diverge, describing a regular curve outward, and 

 again converge to their cloacal terminations. 



In the Salamander (Salamandra maculosa) the oviduct is more 

 definitely divided into an oviducal, or ' fallopian,' and a uterine 

 part: the former, fig. 394, a, is slender, and before impregnation 

 is convoluted to within a short distance of the cloaca, where it 

 suddenly expands into the uterine part, b : this part curves for- 

 ward and outward before terminating in the cloaca at c. The 

 young are developed in this expanded part of the oviduct, which 

 is much enlarged after impregnation, as in the figure. 



In the tailless Batrachia the ovary, in its quiescent state, fig. 

 395, o, has the form of an irregularly plicated membranous sac, 

 with thin and transparent parietes. The initial aperture of the 

 oviduct, ib. a, is situated close to the base of the heart : the tube 

 is disposed in many, usually transverse, folds or coils, before its 

 termination in the dilatable terminal part, in which the ova to be 

 impregnated and discharged in the same season are accumulated, 

 as in fig. 395, b. In the cloaca the following outlets are seen : — 

 in front, that of the allantoic bladder, behind it that of the 

 rectum, then the oviducal outlets, ib. c, and lastly those of the 

 ureters. 



