238 STUDIES ON PATHOLOGIC OVA. 



accessions of tubes received through the unselfish efforts and the scientific interest 

 of practitioners in all parts of the nation. 



In addition to over 100 free specimens of uterine hydatiform degeneration, 

 I have also seen more than a dozen fine specimens in large sections of uterine 

 implantation sites, and some entire specimens still embedded in pregnant uteri and 

 tubes. Indeed, how many cases of hydatiform degeneration one can find in con- 

 ceptuses in tubal or hysterectomy specimens will depend very much upon the care 

 with which the examination is made, for the condition undoubtedly is extremely 

 common, and not rare, as heretofore supposed. 



Although the alleged menstrual age of these conceptuses ranged approximately 

 from 6 to 218 days, most of them were young empty chorionic vesicles or mere 

 remnants of such. Portions of quite a number were still implanted within the tube, 

 however, and among these were two unusually fine ones in a rare specimen of twin 

 pregnancy in a tube donated by Dr. Cecil E. Vest, of Baltimore. Since the ques- 

 tion of superfetation has been raised also in connection with twin tubal pregnancies, 

 I hasten to add that such a phenomenon, even if it ever occurs (which seems exceed- 

 ingly doubtful), can be excluded absolutely in this case. Both chorionic vesicles 

 were approximately of the same size and lay in practically the same cross-section 

 of the tube, the surfaces of contact being flattened. 



There were 40 tubes containing villi only, and in 14 of these hydatiform 

 degeneration probably was present. In 10 specimens its presence was undoubted, 

 but in 4 it was probable only. I realize that this margin of probability is exceedingly 

 large, but this is easily understood if it is recalled that often only a few degenerate 

 villi embedded in clot were contained in the cross-sections of the tubes, and that 

 only a few sections were examined, not, of course, a complete series of each tube. 

 Had the entire tubes been examined, or if more villi had been present, and if 

 those present had been better preserved, the difficulty would have been almost 

 wholly obviated. However, it is idle to set forth these things, because such con- 

 ditions never will obtain, and the margin of probability becomes greatly reduced 

 if it is remembered that in a large series the specimens necessarily supplement each 

 other. Moreover, the changes in the villi often are so typical that they are unmis- 

 takable, even if only a few villi are present. Besides, examination in complete 

 series undoubtedly would increase, not decrease, the number found. In some of the 

 doubtful cases the existence of hydatiform degeneration became probable only 

 upon comparison with the many uterine specimens previously examined. 



The evidence offered by the 36 tubal specimens in the second group, which is 

 composed of empty chorionic vesicles or parts thereof, was very conclusive, for the 

 cut portions of most of these tubes contained considerable portions or even sections 

 of whole chorionic vesicles, sometimes quite free from clot. Some of them were 

 implanted almost perfectly in the wall of the tube, and although many of them 

 were folded extremely and collapsed more or less, small areas of several were never- 

 theless implanted undisturbed within the tube. The villi in some of these implanted 

 specimens were so characteristic and the whole picture so exquisite that the spec- 

 imens rightly belong among the very finest instances of hydatiform degeneration 

 found anywhere so far. This is true in particular of the case of twin pregnancy re- 



