366 



HUMAN UTERUS AND FETAL APPENDAGES. 



the trophoderm we find great masses of cells somewhat similar to those of the 

 cellular layer upon the chorionic membrane and over the surface of the villi, but 

 they are larger and more lightly stained. They lie closely packed together; their 

 nuclei are rounded in form, but vary considerably in size and shape. Many of 

 them contain one or two distinct spots, which, however, are sometimes absent. 

 On the edges of the spaces which have been formed, and sometimes apparently 

 in the interior of the mass of trophoderm, we find bands and lines of degenerative 



EC'. 



EC". 



Tro. 



FIG. 243. PORTION OF THE PRECEDING FIGURE MORE HIGHLY MAGNIFIED. 



deg, Degenerating ectoderm. EC', Outer syncytial layer of ectoderm. EC", Inner cellular layer of ectoderm. 

 mes, Mesoderm of villus. Tro, Trophoblast. X 350 diams. 



material in which we can find nuclei, but no distinct cell boundaries. The 

 substance between the nuclei is more or less uniformly granular in texture and 

 stains quite deeply. The nuclei of the degenerative material vary extremely in 

 appearance. In some cases they are small and stain rather deeply, and are then 

 found to be present in more or less considerable numbers. Occasionally, however, 

 the nuclei are much larger, and more rarely one sees a nucleus of exceptionally 

 great diameter. 



