Prof. Owen's Description of the Lepitlosiren annectens. 349 



tliree-sided, with their broadest flattened surface turned forwards and covered 

 by the peritoneum. The ureter* runs along their posterior and outer edge, 

 and opens into the common termination of the oviducts. The kidneys are 

 surrounded by a capsule of cellular membrane, beneath which there is a 

 quantity of intense black pigment : the same pigment is developed from the 

 membrane surrounding the oviducts above the kidneys. There is a small Al- 

 lantoid bladder f. 



Generative System. 



The ovaria| are compressed bodies between four and five inches in length, 

 situated, as above described, at the sides of the abdominal cavity ; having a 

 proper capsule beneath the serous investment, and witli their posterior extre- 

 mities continued a little way beyond the posterior line of reflection of the 

 peritoneum. The ovisacs exhibited diffierent stages of development : those on 

 the posterior part of the ovarium were larger than those on the anterior. The 

 larger ova are from one line to two lines in diameter; these were scattered 

 througliout the whole length of ovary, and were separated by clusters of smaller 

 ovisacs varying in size from one twentieth of an inch to invisible minuteness. 

 The oviducts^ are long, tortuous, and commence each by a distinct aperture 

 at their anterior part, which is in the form of a slit, about three lines in length ||. 

 The oviduct is closely attached throughout the greater part of its course to 

 the outside of the capsula ovarii : its tunics gradually increase in thickness as 

 it approaches the cloaca, but are nowhere complicated with a special glandu- 

 lar apparatus. The internal surface of the lower third of the oviduct presents 

 small parallel oblique laminae, like those in the uterus of the Shark. The two 

 oviducts unite and form one strong muscular canal between the allantois and 

 the ureters ; and after receiving the contents of these parts, the common canal 

 terminates in the posterior part of the cloaca. 



Thus the female organs of geneiation in the Lepidosiren, both as regards 

 the condition of the ovaria, caused by the partial or successive development of 

 the ova, and the freedom of the oviduct, present a grade of development as 

 high as that which characterizes the Plagiostomous Fishes ; while the elongated 



* Tab. XXVII. fig. 7, i. t lb. k. \ Tab. XXV. tig. \.g., and Tab. XXVII. fig. 'J. I. 



§ Tab. XXVII. fig 7, m,m. \\ lb. n.n. 



