PLATE II 



FIG. i. Human blood (Nocht-Romanowsky stain), X 335. Ewing. 



This figure shows the red blood-corpuscles (erythrocytes), two clumps of platelets near the 

 centre of the field and to the right and one large mononuclear leucocyte. The outlines of the 

 leucocyte are faint and the nucleus is stained a dark purple. 



FIG. 2. Hemin crystals, X 500. Schultze. 



This specimen was prepared from a human blood-stain on muslin, 48 hours old. The spot 

 was extracted with a 1-2000 salt-solution. 



FIG. 3. Human heart-muscle (hematein and eosin), x 125. Ferguson. 



This figure shows the branching and inosculation of the fibres of the heart-muscle. 



FIG. 4. Cross-section of the trachea of the dog (hematoxylin-eosin), x 20. Author's 

 collection. 



At the top of this section is the layer of epithelium, darkly stained, covering the mucosa ; 

 below is the submucosa, with three mucous glands ; below, stained blue, is the cartilage, with 

 the perichondrium next the submucosa ; beneath the cartilage is the outer fibrous coat. 



FIG. 5. Section of the lung of a sheep, injected, X 75. Author's collection. 



This figure shows the bloodvessels, especially the capillaries. The large vessel at the lower 

 part is a branch of the pulmonary artery ; the large vessels near the upper border and to the 

 right are branches of the pulmonary veins ; some of the rounded or ovoid spaces, each bounded 

 by a ring of capillaries seen vertically, are alveoli, one of these being nearly in the centre of the 

 field. 



P'IG. 6. Section of the lung of a child (hematoxylin-eosin), X 125. Ewing. 



The larger spaces shown in this section are the infundibula ; the smaller spaces are 

 alveoli, some opening into infundibula and some surrounded by the pulmonary tissue ; at the 

 top of the figure, part of a bronchiole, lined with epithelium, is seen. 



