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STUDIES ON PATHOLOGIC OVA. 



In determining normality, the criterion used was the shape of the embryo, 

 judging this as best we could by our own knowledge of human and comparative 

 embryology, as well as by the experience of other students of human embryology. 

 We have also used freely the atlases of His, Hochstetter, and Keibel and Else in 

 making our decisions on this point. However, many of these specimens are inclosed 

 in membranes which have undergone very marked changes. Thus, an embryo 

 normal in form may be found to be surrounded by an excessive amount of magma 

 and the chorion may have undergone very pronounced changes; but for purposes 



TABLE 8. Distribution of uterine specimens. 



TABLE 9. Distribution of ectopic specimens. 



of classification we have found it necessary to arrange them all according to the 

 shape of the embryo. A fairly large number of our specimens were obtained from 

 hysterectomies. We believe with Hochstetter that we shall ultimately have to 

 determine what constitutes a normally formed human embryo from specimens 

 obtained in this way; but among about 25 hysterectomy specimens, we never- 

 theless found 3 which were markedly pathological and undergoing abortion. 



Table 8 includes all uterine and table 9 all ectopic specimens. In comparing 

 these three tables it will at once be noted that among the entire 1,000 nearly 40 

 per cent are pathological embryos and ova. Of this number 31 per cent were 



