. Discovery reports. Discovery (Ship); Scientific expeditions. THE REPRODUCTIVE ORGANS 383 (a) Growth of the Ovaries In discussing the physiology of the ovaries it will be convenient to start with an account of their growth in the foetus and the young whale. In Blue and Fin whale foetuses measuring about i m. they are small elongated bodies whose flattened surfaces are marked by a number of furrows (Fig. 118). The whole genital tract of the young foetus at this stage is engorged with blood so that the ovaries are of a deep red colour. In larger foetuses the furrows are more pronounced and more
. Discovery reports. Discovery (Ship); Scientific expeditions. THE REPRODUCTIVE ORGANS 383 (a) Growth of the Ovaries In discussing the physiology of the ovaries it will be convenient to start with an account of their growth in the foetus and the young whale. In Blue and Fin whale foetuses measuring about i m. they are small elongated bodies whose flattened surfaces are marked by a number of furrows (Fig. 118). The whole genital tract of the young foetus at this stage is engorged with blood so that the ovaries are of a deep red colour. In larger foetuses the furrows are more pronounced and more numerous (Plate XXXIX, figs. 3 and 4). After the calf is born the majority of the furrows are smoothed out by the growth of the ovaries, but some remain to mark the convolutions of the adult ovary which are referred to above, and some of the minor furrows occasionally persist to give the surface of the ovaries a curious appearance which has been described in notes on the internal genitalia as "; This is illustrated in Fig 119 and Plate XXXIX, fig. Fig. 118. Ovary of foetus measuring i-i3 m. (Natural size.) Fig. 119. Small portion of ovaiy of immature whale, showing "bramble ; >: 1-5. Although the ovaries do not grow very much from birth to sexual maturity, consider- able changes take place. From rather rounded, soft structures they become pale, flat, compact organs (Plate XL, fig. i). They remain, however, small up to this stage, for in Fin whales measuring less than 18 m. and in Blue whales under 20 m. the two ovaries together weigh less than i lb. The ovaries of immature Fin whales practically never weigh more than 2 lb., nor those of Blue whales more than 3 lb. After sexual maturity is reached the weight of the ovaries, as shown in Figs. 120 and 121, appears to increase up to a point with the increasing length of the whale. Although the ovaries of large whales are as a rule bigger than those of smaller whales, the increase
Size: 1432px × 1745px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectscientificexpedition
