Jump to content

Page:GrouseinHealthVol1.djvu/131

From Wikisource
This page has been proofread, but needs to be validated.
LOCAL VARIATION IN THE PLUMAGE GROUSE
61

with birds found dead of disease in April and in May, the discovery of the ovary is still a matter of comparative ease, and the discovery of the testes even easier. The testes are always somewhat enlarged in the spring months, whether the bird be diseased or not, and they may be the size of a pea or larger, and will generally be white. The ovary may be small, but will always be like a portion of hard cod's roe, in which the ova, though no bigger than a pin's head, are distinct and numerous. The undeveloped ovary of an adult female Grouse would about cover a threepenny piece, but is long and triangular in shape rather than circular.

The oviduct in a breeding hen is a large and conspicuous duct, and may, of course, contain an egg with the shell in course of formation, being pigmented in preparation for laying. The oviduct in a barren bird, or in a hen at other times than the breeding season, is a very much less conspicuous object, and is less easily found than the small and undeveloped ovary.

If no ovary is seen, but a very small blackish, or whitish, or particoloured object is found in its place which is suspected of being a testis, the intestines must then be gently separated from their attachments about the middle line of the back, and the other testis must be sought for in about the same position on the opposite side. Even in a young bird the ovary shows ova with sufficient distinctness to make doubt as to its sex an impossibility; but in a very young male bird the testes may be so small, and, being very often black, may look so unlike what is expected that both should be sought for and found before arriving at a certain conclusion as to sex.

It is easy, if the intestines are roughly handled, and the attachments torn carelessly away, to carry away the testes or the ovary from their proper position, and to remove them with the intestinal attachments. The peritoneal folds are delicate and require careful handling, and they overlie the generative organs and the kidneys; but a very little practice will enable any one to do the necessary dissection with certainty, and to arrive at an irrefutable diagnosis as to sex.

It may be said that there is no other infallible means of arriving at the sex of a Grouse at certain times of the year, for it has so often happened that experienced and careful gamekeepers, who have handled Grouse for a lifetime, have certified a specimen as a cock, when the specimen has turned out to be a hen, and vice versa. The mistake is unavoidable and excusable,