This "vagina" is sometimes of exaggerated size.
The two ducts continuous with the gonads open by a common vagina on to the exterior behind the male pores.
Usually they open into a median vagina, formed by an ectodermal inpushing and lined with chitin.
The vagina usually opens in front of the eighth abdominal sternite.
The perchloride, sulphate and pernitrate are strongly astringent; less extensively they are used in chronic discharges from the vagina, rectum and nose, while injected into the rectum they destroy worms.
From this vagina arises a narrow duct leading to the exterior.
The vagina is a dilatable muscular passage, lined with mucous membrane, which leads from the uterus to the external generative organs; its direction is, from the uterus, downward and forward, and its anterior and posterior walls are in contact, so that in a horizontal section it appears as a transverse slit.
Owing to the fact that the neck of the uterus enters the vagina from in front, the anterior wall of that tube is only about 21 in., while the posterior is 31.
The relation of the vagina to the peritoneum is noticed under Coelum and Serous Membranes.
The hymen is a fold of mucous membrane which surrounds the orifice of the vagina and is usually only seen in the virgin.
The glands of Bartholin are two oval bodies about half an inch long, lying on each side of the vagina close to its opening; they represent Cowper's glands in the male, and their ducts open by minute orifices between the hymen and the labia minora.
From the above description it will be seen that all the parts of the male external genital organs are represented in the female, though usually in a less developed condition, and that, owing to the orifice of the vagina, they retain their original bi-lateral form.
They are also employed locally as sprays and douches to the nose, throat, vagina and rectum, for catarrhal conditions of the mucous membranes.
The vagina is often partially divided by a membraneous septum or hymen.
The median vagina, spermatheca and ejaculatory duct are, on the other hand, formed by ectodermal inpushings.
The independent opening of the genital ducts and the absence of an ectodermal vagina and ejaculatory duct are remarkable archaic features of these insects, as has been pointed out by J.
In addition to this, its long axis forms a marked angle with that of the vagina, so that the whole uterus is bent forward or anteverted.
The large sacs which have been termed vagina are suggestive of the large coelomic spermathecae in Eudrilids, a comparison which needs, however, embryological data, not at present forthcoming, for its justification.
In it the hairs are confined to the dorsal middle line and the creeping setae are hooked, of a finer structure than in Chaetosoma, and situated so far forward that the vagina opens amongst them.
In the vast majority of winged insects the terminal part of the genital system (vagina and ductus ejaculatorius) is unpaired and ectodermal.