298 On the Female Organs and Placentation of the Racoon. 



Figure 3, The placenta, showing the central gap which corresponds to the attach- 

 ment of the amnion, as shown in fig. 2. 



Figure 4. The foetus with its epitrichial investment. The latter has been slit open 

 along the ventral surface of the animal. 



Plate 4. 



Figure 5. Interior of the gravid uterus of Proeyon lotor, two-thirds natural size. 



In the right cornu uteri the foetus is shown enveloped by the chorionic 

 membrane and surrounded by an annular or zonary placenta. The 

 left cornu uteri is opened to show the trans versely- arranged mucous 

 folds. Between the cornua is the septum uteri, o.u. Os uteri, pro- 

 vided with a valve-like fold of mucous membrane, which separates 

 the uterus from v. the vagina. v.G.c. Urogenital canal laid open. A 

 bristle is passed into the urethra. Other letters as in fig. I, Plate 3. 



Figure 6*. Left cornu uteri, natural size, seen from above. The drawing shows the 

 abdominal opening of the Fallopian tube and the relations of that tube to 

 the ovary, o. Ovary, c.tt. Cornu uteri, l.d. Ligamentum diaphragmati- 

 cum uteri, e.t. Fallopian tube. 



Figure 7. Surface view of portion of the mucous membrane from the placental site 

 of the gravid horn, slightly magnified. 



Figure 8. Section of wall of barren horn of uterus, to show the uterine glands. 

 Magnified 55 diameters. 



Plate 5. 



Figure 9. View of uterine surface of the detached placenta, showing the honeycomb 

 appearance, slightly magnified. 



Figure 10. Horizontal section (i.e., the line of section was parallel to the surface of 

 the organ) of the placenta, showing the colossal capillaries, for the 

 most part divided transversely, magnified 235 diameters. 



Figure 11. Portion of the placental substance, teased out after being submitted to the 

 action of dilute sulphuric acid. The figure shows the structure of the 

 colossal capillaries, their endothelial lining, and the mode of anastomosis 

 between them, magnified 235 diameters. 



Plate 6. 



Figure 12. Longitudinal vertical section (i.e., the line of section was at right 

 angles to the surface of the organ) of the placenta, showing the colossal 

 capillaries, for the most part divided longitudinally, magnified 235 

 diameters. 



Figure 13. Transverse vertical section of the placenta, showing the colossal capillaries 

 with the intervascnlar matrix. The capillaries are for the most part 

 divided longitudinally, magnified 235 diameters. 



