842 THE FEMALE GENITAL TEACT. 



basis-substance, we always see numerous fine threads projecting into the 

 basis-substance, where they are lost to sight. 



In the fully developed decidua the details in the structure are exactly the 

 same as in the 'growing placenta, with one exception viz. : that multinuclear 

 masses are absent ; the meshes of the myxomatous basis-substance contain- 

 ing roundish plastids, mainly devoid of nuclei, while numerous meshes, sur- 

 rounded by a dense, highly refracting net-work of the basis-substance, look 

 homogeneous and structureless. The basis-substance assumes, in the adven- 

 titial layer of the arteries, a decidedly fibrous structure, which again proves 

 to be constructed by bundles of minute spindles, in the narrow and elongated 

 meshes of which granular bioplasson is to be seen. The interstices between 

 these spindles of the fibrous basis-substance are also traversed by minute ver- 

 tical threads. 



The history of the development of the basis-substance has always been a 

 matter of careful study with our best histologists. Now, the placenta offers 

 an excellent means of settling several points of discussion, both on account 

 of the relatively short time required for its formation, and the clearness of the 

 relation between the protoplasm and the myxomatous basis-substance. 



The manner of formation of the myxomatous basis-substance of the pla- 

 centa is as follows : 



The formative elements appear in the shape of multinulear bodies, exactly 

 like those in developing bone or cartilage where the so-called "giant-cells" 

 prove to be the forerunners of the forming basis-substance. The next step is 

 the formation of bioplasson layers, in which nuclei are no more recognizable, 

 while the net-work of living matter is arranged mainly in a longitudinal direc- 

 tion viz.: in the shape of closely packed spindles. In the next stage the 

 fluid part of the plastids is transformed, chemically, into a shining, highly 

 refracting basis-substance which hides the living matter, this being demon- 

 strable only in the interstices between the delicate spindles in the shape of 

 minute grayish threads. 



The most solid part of the basis-substance, as represented by the fibrous 

 tissue of the adventitia of the arteries, originates in the same way as the 

 myxomatous basis-substance of the stroma of the decidua. The only differ- 

 ence is that the groups, respectively the net-work of the living matter, are 

 more elongated in the adventitial fibrous than in the myxomatous reticular 

 tissue. In both instances the meshes hold a certain amount of unchanged 

 bioplasson, which is relatively profuse in the myxomatous tissue and scant in 

 the fibrous. Even in the latter tissue we find larger and more numerous bio- 

 plasson masses in the decidua of the placenta, advanced only to the fifth or 

 sixth month of development, than in the decidua fully ripe for elimination 

 from the maternal body. 



WAXY DEGENERATION OF THE PLACENTA. BY JEANNETTE 

 B. GREENE, M. D., NEW-YORK.* 



My attention was drawn by Dr. Heitzmann to the fact that specimens of 

 placenta from cases of premature birth and abortion, which had been pre- 

 sented to him by different physicians, exhibited peculiar changes in their 



* Abstract of the author's essay. American Journal of Obstetrics and Diseases of Women 

 ana Children, vol. xiii., 1880. 



