ISC PLLCEXTA. 



first imtawy there are filiform solid villi ; these subsequ 

 become thicker, then contain many nuclei then have a cavity 

 in their interior, and finally have an investment of columnar 

 cells smTounding the cavity. 



I must further remark, that I have in many instances seen 

 the border bounding the villi externally, and describee 

 Goodsir* and Schroder Tan der Kolkf as an independent 

 membrane, raised up and isolated from the matrix; and in 

 such cases I repeatedly saw the nuclei separated from the 

 border bj a more or less thick layer of matrix. I do not 

 know whether the limiting membrane exists during life. In 

 fresh vifli no double contour is apparent, even when they are 

 examined with the best microscopes. The membrane, which 

 may be found partially detached when Jassmsky's method 

 (maceration in "hydrochloric acid} is employed, may also be 

 a product of the coagulation of the superficial layer of proto- 

 plasm. It is moreover not probable that a membrane should 

 form upon the threads protruded from the protoplasm, since 

 one is subsequently seen investing the free extremities of the 

 s"i r -r r : i;\l ; : LM n n xi : - 11 ^ 



The vessels of the villi are not in direct contact with the 

 watt of the viflus. but rather float in a cavity of the villas, 

 which may thus be termed a peri vascular space. This cavity 

 is usually widest at the ends of the villi, and in the vilius- 

 protrusions into which the vessels only just enter. 



Schroder van der Kolk was the first to demonstrate that the 

 arteries and veins in the vifli do not form simple loops, but are 

 connected by a dose capillary plexus. 



The connective tissue of the chorion penetrates with the 

 vessels into the interior of the villi On the pedicles of the 

 villi it exhibits a distinctly fibrous structure (Yireho w's mucous 

 tissue), but near the extremities of the vifli it appears as 

 structureless intercellular substance in which no indications of 

 a fibrous structure are perceptible. 



Bound, fusiform, and stellate cells are distributed through 



+ Am* m* ML 

 AfWi 1 



