REPRODUCTIVE ORGANS 



755 



opens into the coelom. The first part of the oviduct is a 

 funnel or ostium tubas, which grips the ovum and probably 

 forms the thin (chalaziferous) layer of dense albumen next 

 the yolk. The second part is the albumen-secreting 

 portion, which forms dense albumen. The third portion, 

 called the istnmus, makes the shell-membrane and more 



SR. 



rroi 



Fig. 452.^ — Female urinogenital 

 organs of pigeon. 



K., Kidney with thiree lobes ; u., 

 ureter ; cl., cloaca ; ov., ovary ; 

 od,., oviduct ; f.i., funnel at end of 

 oviduct ; r.r.od., rudimentary right 

 oviduct. 



Fig. 453. — Male urinogenital 

 organs of pigeon. 



T., Testes ; V., base of inferior vena 

 cava ; S.R., suprarenal bodies ; K., 

 kidneys with three lobes (i, 2, 3) ; 

 u., ureter ; v.d., vas deferens ; v.s., 

 seminal vesicle ; cl., cloaca. 



albumen. The fourth region, badly called the uterus, 

 makes the shell and 30-40 per cent, of the albumen, which 

 passes by diffusion through the shell-membrane before the 

 shell is formed. The fifth portion, called the vagina, is 

 very muscular and expels the egg. It has only unicellular 

 glands which perhaps secrete the external cuticle of the 

 shell, plus pigment. 



