366 



TELEOSTEI 



Haller [193], Howes, Felix [136]). We may here briefly discuss 

 their morphology. In both sexes the gonads arise as a longitudinal 

 thickening of the coelomic epithelium, near the base of the mesentery, 

 which hangs in the body -cavity as the genital ridge (Fig. 338). 

 On the outer side of this fold the genital cells are developed. 



First of all with regard to the absence of a direct communi- 



msd. 



upr- 



Fio. 355. 



Diagrams of the female urinogenital ducts in the Dipnoi and Teleostomi derived from the 

 figures of various authors. A, Protoptcrus (after Ayers and W. N. Parker). U, Pdypterus (after 

 Budgett). C, Amia (after Hyrtl and Huxley). D, Lepidosteus (after Balfour and Parker). E, 

 a Teleost with closed ovisac. F, a Salmonid (after Weber). a.p, abdominal pore ; c, cloaca! 

 bladder; cZ, cloaca;/, open funnel of oviduct; k, mesonephros ; ms.d, mesonephric duct; o, 

 ovary ; od, oviduct ; op, genital papilla and pore ; ovs, closed ovisac ; r, rectum ; ug.p, urino- 

 genital papilla ; u.p, urinary pore. In all the figures, except F, only the right oviduct is com- 

 pletely drawn. 



cation between the testis and the mesonephros, characteristic of all 

 the Teleosts. This is doubtless secondary. A system of spaces and 

 canals develops from the testis, and from these is formed near the 

 base of the peritoneal fold supporting the testis a longitudinal duct 

 which grows back to the external opening (Fig. 356, B). It seems 

 very probable that this sperm-duct represents the longitudinal canal 

 found in other Gnathostomes uniting the testicular canals, and into 



