HOW TO DETERMINE THE SEX OF A BIRD. 31 
In the female, in the breeding -season, on the left side of the body, 
in a position corresponding to that of the testes of the male, there 
will be found a large yellowish mass, made up of eggs of various 
sizes, from tiny granules to a full-sized yolk (fig. 5, ovy.). Earlier in 
the year the mass is granular only, and of course much smaller, 
Fig. 4.— A portion of the body-cavity of a 
bird exposed to show the position of the 
male sexual organs, s.r. suprarenals, or 
adrenals ; t. testes ; k. kidney ; vd. vas 
deferens, or sperm-duct ; int. intestine. 
Fig. 5.— A portion of the body-cavity of a 
bird exposed to show the position of the 
female sexual organs. lg. lung ; k. kidney ; 
ovy. ovary ; ov.d. oviduct. 
sometimes extremely small. If the ovary has been destroyed by shot, 
or is, as often happens, but slightly developed, look carefully on the 
left side of the body for a long and more or less coiled tube (the 
oviduct), one end of which— that towards the head— is free, the other 
joined on to the intestine, quite close to where it leaves the body 
(fig. 5, ovd.). A vestige of a similar small tube will be found in the 
