672 THE GENERATIVE ORGANS. 
their widest part. The azygos oviduct in the same condition 
is about 2 mm. in length, and is nearly 1 mm. in breadth when 
seen flattened out after dissection. During the transit of the 
ova the oviducts become greatly elongated; the tube usually 
each contain an ovum, whilst the azygos oviduct often contains 
‘ D 
wees 
> |e 
Fic. 94.— Transverse sections of the parovaria of the Blow-fly. 4, section 
through a mature parovarium; A, a single cell from the same, showing 
the included corpuscle, the germ ovum, and the nucleus; C, a section of the 
parovarium in a less developed condition ; D, a section showing the adjacent 
fat body ; Z, section through an immature parovarium. All the figures except 
D represent the structures as they appear with a yy oil-immersion objective. 
J; fat-cells ; x, nuclei ; 0, germ ovum ; 2, vitelline vesicle ; s, zona radiata. 
two or three, so that the whole length of the tube must exceed 
4mm. And sections show that its course is exceedingly tor- 
tuous. The ducts of the parovaria open into the anterior 
part of the sacculus. 
The Parovaria.—The glands which I term parovaria in the 
Blow-fly are simple tortuous, rather than convoluted, tubes, 
