HOW TO DETERMINE THE SEX OP 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 Fig. 5. — A portion of the body-cavity of a 
bird exposed to show the position of the bird exposed to show the position of the 
male sexual organs, s.r. suprarenals, or female sexual organs. Ig. lung ; k. kidney ; 
adrenals ; t. testes ; k. kidney ; vd. vas ovy. ovary ; ov.d. oviduct, 
deferens, or sperm-duct ; int. intestine. 
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 
