. Fig. 25—Diagram of ovary of cow showing comparative sizes of the follicles shown in Figs. 22, 2a, 24 The number of ovisacs rupturing at a given estrual period corresponds as a rule with the maximum number of possible fetuses. It is said that rarely two ova are contained in one ovisac. I have been unable to verify this statement, and have in all cases of twins in the cow observed two corpora lutea, sometimes both in one ovary but most frequently one in each. Sometimes a single fertilized ovum divides to con- stitute two embryos, which form identical twins in man, but this is not known to occu
. Fig. 25—Diagram of ovary of cow showing comparative sizes of the follicles shown in Figs. 22, 2a, 24 The number of ovisacs rupturing at a given estrual period corresponds as a rule with the maximum number of possible fetuses. It is said that rarely two ova are contained in one ovisac. I have been unable to verify this statement, and have in all cases of twins in the cow observed two corpora lutea, sometimes both in one ovary but most frequently one in each. Sometimes a single fertilized ovum divides to con- stitute two embryos, which form identical twins in man, but this is not known to occur in domestic animals, though it probably does so. In multipara, it is assumed that there are at least as many ova discharged, from as many ovisacs, as there are embryos.
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Keywords: ., bookauthorwilliams, bookcentury1900, bookdecade1920, bookyear1921
