1 2 ELEMENTS OF HISTOLOGY. [Chap. n. 



become smaller and spherical, but beset all over their 



surface with minute processes. This shape is called the 



horse-chestnut shape (Fig. 8, b, c). It is pro- 



Q Q bably due to the corpuscles losing carbonic 



acid, as its addition brings back their discoid 



shape and smooth circular outline. On ab- 



W w stracting the carbonic acid they return to 



ft the horse-chestnut shape. Water, acid, 



'fed Biood alcohol, ether, the electric current, and 



a crenat^T c manv other reagents, produce discoloration 



'shSed! h ^ st " u * ^ * ne re d blood corpuscles ; the colouring 



matter generally the combination of 



the blood-colouring matter with globulin known as 



hcemoglobin becoming dissolved in the plasma. 



What is left of the corpuscles is called the 



stroma. In newts' and frogs' blood a separation of 



the stroma from the 



nucleus plus haemoglobin 



can be effected by means 



of boracic acid (Fig. 9, B) ; 



the former is called by 



Briicke the Oikoid, the 



-, , , r , . -. mi . Fig. 9. Bed Blood Corpuscles of 



latter Zooid. This stroma Man and Newt; 



Contains amongst Other A, Human red corpuscles after the action 



r j j i of tamric acid : n, three red cprpuscles, 



tningS a gOOQ Cleal Ot para- from which the haemoglobin is passing 



-i -T rm u t ; &, Roberta's corpuscles. 



globulin. I he Stroma B, Newt's red corpuscles after the action 



, i i of boracic acid : a, a corpuscle showing 



OI tne COrDUSCleS OI BrUckes' zooid and oikoid ; 6, a corpus- 



-i .-, . . cle showing the reticulated stroma; 



amplllDiailS IS Seen, c, a corpuscle showing the reticulum 



i , . in the nucleus ; d, the nucleus passing 



under certain reagents, out. 

 to be of a reticulated 



structure, but in the fresh state appears homo- 

 geneous and pale. Discoloration of the blood cor- 

 puscles can be observed to take place also in blood 

 without the addition of any or with that of per- 

 fectly harmless fluids, such as humor aqueus of 

 the eye, hydrocele fluid, &c. The number of cor- 

 puscles undergoing discoloration is, however, small. 



