URINARY DUCTS OF THE FEMALE. 483 



shewn by Semper, rudiments of the upper extremities of the 

 oviducts, with their abdominal openings, are to be found in the 

 male in the same position as in the female, on the front surface 

 of the liver. 



In the female the same ducts are present as in the male, 

 viz. the Wolffian duct and the ureters. The part of the Wolffian 

 duct which receives the secretion of the Wolffian body is not 

 contorted, but is otherwise similar to the homologous part of 

 the Wolffian duct in the male. The Wolffian ducts of the two 

 sides fall independently into an unpaired urinal cloaca, but 

 their lower ends, instead of remaining simple as in the male, 

 become dilated into urinary bladders. Vide PI. 20, fig. 2. There 

 were nine ureters in the example dissected, whose arrangement 

 did not differ greatly from that in the male the hinder ones 

 remaining distinct from each other, but a certain amount of 

 fusion, the extent of which could not be quite certainly ascer- 

 tained, taking place between the anterior ones. The arrange- 

 ment of the openings of these ducts is not quite the same as in 

 the male. A somewhat magnified representation of it is given 

 in PI. 20, fig. 3, o. 21. The two Wolffian ducts meet at so acute 

 an angle that their hindermost extremities are only separated 

 by a septum. In the region of this septum on the inner walls 

 of the two Wolffian ducts were situated the openings of the 

 ureters, of which there were five on each side arranged linearly. 

 In a second example, also adult, I found four distinct openings 

 on each side similarly arranged to those in the specimen de- 

 scribed. Professor Semper states that all the ureters in the 

 female unite into a single duct before opening into the Wolffian 

 duct. It will certainly surprise me to find such great variations 

 in different individuals of this species as is implied by the dis- 

 crepancy between Professor Semper's description and my own. 



The main difference between the ureters in the male and 

 female consists in their falling into the urinogenital cloaca in 

 the former and into the Wolffian duct in the latter. Since, 

 however, the urinogenital cloaca is a derivative of the Wolffian 

 duct, this difference between the two sexes is not a very im- 

 portant one. The urinary cloaca opens, in the female, into the 

 general cloaca by a median papilla of somewhat smaller di- 

 mensions than the corresponding papilla in the male. Seminal 



