221 



as a narrow tube extending forward about as far as the anterior end 

 of the kidneys, and is but a small fraction of the size and length of 

 the functional right oviduct (Figs. 1, 2). Instead of having a broad 

 ostium, its anterior end is narrowed considerably, and either ends 

 blindly or, possibly, has a minute anterior opening. Although it is 

 quite incapable of receiving or supporting an egg, it nevertheless 

 retains its central lumen, and is provided with numerous glands 

 similar to those of the functional oviduct. The secretions from these 

 glands are doubtless discharged into the cloaca. 



Both oviducts open near the median line on the dorsal side of a 

 horizontal shelf which divides the anterior portion of the cloaca into 

 a dorsal and a ventral chamber. The openings do not differ in size, 

 nor is the functional oviduct greatly larger in its narrowed terminal 

 portion than the aborted one. Each opens at the summit of a short 

 papilla, and these are likewise of about equal size. 



The aborted oviduct thus appears to have retained in some 

 measure its secretory function, even though it is of little importance 

 in the economy of the body. Like many structures which show evi- 

 dence of recent degeneration this rudimentary organ exhibits a very 

 considerable variation in length and size in diflerent individuals. While 

 its average length is about equal to that of one of the kidneys, yet 

 in several instances it has been found to be much shorter, and in a 

 single case observed it was considerably-longer than usual, and had a 

 distinct anterior ostium. It is conceivable that in an exceptional case it 

 might actually remain of sufficient size to receive and support an egg. 



It should be noted that in the closely allied Anguis both ovi- 

 ducts are well developed, and both bear an approximately equal 

 number of embryos, some 15 to 20 young being produced in a single 

 season ^). In Amphisbaena both oviducts are hkewise of about the 

 same size 2), as is also the case in Anops and Trogonophis ^). 



1) Leydig, Die in Deutschland lebenden Arten der Saurier, 1872, 

 p. 180. 



2) Bedriaga, Arch. f. Naturgesch., Jahrg. 50, 1884, p. 67. 



3) Smalian, Zeitschr. f. wiss. Zool., Bd. 42, 1885, p. 191. 



Fig. 1. Female urogenital organs of Anniella pulcbra when not pregnant, 

 showing the comparative size of the functional right oviduct {r.od) and the aborted left 

 oviduct {l.od). r.ov and l.ov right and left ovaries respectively, each of which is pro- 

 vided with a single large egg to be discharged when mature into the ostium (o) of the 

 right oviduct, ad adrenal body, bl urinary bladder, k kidney. ^^ ureter, cl cloaca, i ileum. 

 c rudimentary caecum, r rectum. 



Fig. 2. A similar diagram during pregnancy, showing the swollen uterus {ut) of 

 the right oviduct with the two developing embryos, r.od narrow, anterior portion of 

 right oviduct, with ostium (o). Other reference letters as in Fig. 1. 



