XVI EXPLANATION OF THE PLATES. 



Extremity of a villus, with its absorbent vesicles distended with 



chyle, and the trunks of its lacteals seen through its coats. 

 Protective epitheliuni-cells from a villas in the dog* 

 Protective epithelium-cells cast off preparatory to absorption of 

 chyle ; instead of nuclei, they present, in theii- interior, 

 groujis of globules. 



Fig. 9. A group of the same cells adhering by their distal extremities. 



Fig. 10. Secreting cells throwni out of the follicles of Lieberkiihn 

 during digestion. 



Fig. 11. Diagram of mucous membrane of jejunum when absorption is 

 not going on. a. Protective epithelium of a villus. h. 

 Secreting epithelium of a follicle, c c c. Primary membrane, 

 with its germinal spots or nuclei, d d. e. Germs of absorbent 

 vesicles, f. Vessels and lacteals of villus. 



Fig. 1 2. Diagram of mucous membrane during digestion and absorption 

 of chyle, a. A villus, turgid, erect ; its protective epithelia 

 cast pff from its free extremity ;t its absorbent vesicles, its 

 lacteals and blopd-vessels turgid, h. A follicle discharging its 

 secreting epithelia. 



PEOCESS OF ULCERATION IN ARTICULAR CARTILAGE. 



Plate IV. page 389. 



Fig. 13. a. A section of articular cartilage and absorbent membrane. 

 In the lower part of the section the cartilage - coi^juscles 

 retain their natural size and appearance ; as they approach 

 the rugged ulcerated edge, they increase in size, and contain 

 numerous yoimg cells, apparently the progeny of their nuclei ; 

 beyond this edge, rounded masses of cells, originally con- 

 tained within the cartilage-corpuscles, are seen embedded in 

 the cellular absorbent mass. 

 h. Absorbent cells of the false membrane, with two globular 

 masses derived from the cartilage-corpuscles. 



SECRETING STRUCTURES.— Plates IV. V. 



Plate IV. page 389. 



Fig. 14. Four secreting cells from the ink-bag of Loligo sagitto.ta. 



Fig. 15. Five cells from the liver of Patella vulgata. In this instance 

 the bile is contained in the cavities of the secondary cells, 

 which constitute the nucleus of the primary cell. 



* It may be noted that both in figures 7 and 9 the clear space at the broad free 

 ends of the columnar intestinal epithelial cells, to which several German anatomists 

 have recently directed attention, is figured by the author. — Eds. 



+ The author subsequently abandoned the idea that the epithelial cells were 

 cast off during absorption. — Eds. 



