92 STUDIES ON PATHOLOGIC OVA. 



included with the remaining specimen to make a positive diagnosis justifiable, 

 but the structure of those present did not suggest a hydatiform change. 



The cyemata were all macerated and some were fragmented. In two speci- 

 mens (Nos. 838 and 882), Mall stated that limb-buds were not present. Since 

 the respective specimens were 6 and 8 mm. in length, it is evident that they should 

 have been present, and their absence must be attributed either to inhibition of 

 growth or to disintegration. In the absence of a complete series of sections, this 

 point unfortunately can not be decided. It was possible to recognize outlines of 

 various organs in one specimen only, and since most of the specimens were very 

 young, they had a structure comparable to that of the nodular and cylindrical, 

 rather than of the stunted uterine group. Maceration and dissociation were 

 very marked, as a rule. 



GROUP 7. FETUS COMPRESSUS. 

 A. UTERINE. 



The term fetus compressus was used by Mall in a much more general sense 

 than usual. It has been customary to restrict this term almost wholly to one 

 twin which died early and became softened and compressed by the living, well- 

 developed companion. Instances of a single fetus similar to a true fetus com- 

 pressus are recorded in the literature, however. Strahl and Henneberg (1902), 

 for example, stated that they found such a specimen, although the presence of 

 abnormal pressure exerted directly upon it by the uterus could not be established. 

 Hohlweg (1903) also implied that Kiistner thought that cases of fetus compressi 

 could occur in single pregnancies, and I am quite certain that I am representing 

 Mall correctly when I say that his observations were to the effect that quite typi- 

 cal fetus compressi occur not rarely in single pregnancies in the presence of abun- 

 dant amniotic fluid. Although Schickele (1907) regarded macerated forms from 

 the second months as rare, His (1891) emphasized that the softness of aborted 

 forms easily results in abnormal folds and flexures, and Waldstein (1913) stated 

 that von Winckel found deformities of the extremities extremely common in tubal 

 embryos. 



As previously intimated, this group is a very inclusive one. In some respects 

 it really is a group of left-overs not characterized by maceration alone. Specimens 

 in any of the preceding four groups may be, and indeed they nearly all are macer- 

 ated. However, since many of those in the normal division also are macerated, 

 the presence of maceration can not be regarded as distinguishing any group. 

 Differences in the degree of maceration may and do exist; but since maceration 

 becomes evident externally much more quickly in older fetuses, gross appearances 

 often are a very unreliable guide for the determination of the degree of maceration. 

 One thing, however, is true of all specimens in this group, except such as are com- 

 posed of material from curettage, and that is that maceration often is present 

 even in specimens composed solely of fragments of wholly normal embryos or 

 fetuses. 



Some of the specimens are macerated and swollen and others are shriveled 

 and mummified. The latter Mall distinguished as fetus compressi. The use of 

 this term does not imply, however, that they have necessarily been subjected to 



