244 STUDIES ON PATHOLOGIC OVA. 



nant women. This, however, does not establish the occurrence of ovulation during 

 pregnancy. According to Fraenkel (1910 b ) and Miller (1910), ovulation normally 

 precedes menstruation by about 9 days; but from a study of 100 cases in which the 

 time of occurrence of the menstrual period and the approximate time of coitus were 

 known, Siegel (1915) concluded that ovulation usually occurs between the seventh 

 and fourteenth day post menstruum. Cosentino (1897) and also a few others 

 have reported cases of ovulation during pregnancy in women, but we unfortunately 

 know little as to the exact conditions which obtain, so that the entire matter 

 remains as yet rather undecided. 



Franco (1910), while reporting a case of spurious superfetation, gave a long 

 list of Italian writers who were said to believe in the occurrence of superfetation. 

 Unfortunately, this literature at present is largely inaccessible to me in the original, 

 and such as is accessible remains unconvincing, as all of it apparently seemed to 

 Cuzzi, who is reported by Franco as regarding superfetation only as a theoretical -pos- 

 sibility. Nor does there seem to be good evidence that ovulation occurs during 

 pregnancy in other higher mammals. The only case cited is the questionable one 

 in a cat reported by Christopher (1886) . At present it has not even been established 

 that superfetation occurs in the rare cases of double ovarian or of combined ovarian 

 and uterine pregnancies, although these cases would seem to furnish far more 

 favorable conditions. Did the alleged occurrence of superfetation not involve a series 

 of assumptions each one of which remains unproved, belief in it would seem easier. 

 Consequently, in view of all these things, the conclusion of Gustetter that super- 

 fetation is "a frequent though often overlooked cause" of abortion in women 

 seems rather venturesome, and anyone who critically examines Herzog's (1898) 

 article will see that the evidence he presents really does not justify the claim that 

 it "demonstrates fairly well that there is very little if any reasonable doubt left as 

 to the occurrence of superfetation in the human race." Indeed, although the 

 cases here presented would seem to offer far more conclusive evidence of the 

 occurrence of superfetation than any presented heretofore, there is no doubt that 

 such an interpretation of them would be a mistaken one. 



The possibility of superfecundation, however, is not necessarily excluded by 

 these considerations, for ova from the same ovulation still might be fertilized at 

 somewhat different periods by some spermatozoa from the same or from subsequent 

 coituses. But even while theoretically possible, it is evident that the relatively 

 limited period of vitality of the unfertilized ovum, as contrasted with the duration 

 of pregnancy, would make it extremely difficult, if not impossible, to recognize 

 such cases. This would be true even if they occurred in the earlier stages of devel- 

 opment, for normal growth differences are too great when contrasted with the 

 greatest differences that could possibly exist under these circumstances. This 

 would seem to be true even if we grant that the spermatozoa have a somewhat 

 more tenacious life than ova. Mall (1918) considered evidence which seems to 

 indicate that the life of the fertilizing power, even if not the life of the spermato- 

 zoon, is a decidedly limited one. Hence, if this be true, superfecundation is limited 

 still further as a factor in the problem of superfetation. 



