COLOUEED BLOOD-COEPUSCLES OF AMPHIBIA. 



19 



that of other cells in structure, being bounded by a membrane, and 

 having a network of filaments traversing its interior (fig. 17). It is not 

 very distinct in the unaltered corpuscle, but is brought clearly into 

 view by the action of reagents, especially acetic acid. The action of 

 reagents upon the red corpuscle of amphibia is otherwise similar to that 

 produced upon the mammalian corpuscle, water and acetic acid causing 



FIG. 17. COLOURED 

 CORPUSCLE OP SA- 

 LAMANDER, SHOW- 

 ING INTRANUCLEAR 



NETWORK. (Flem- 



ming.) 



FIG. 16. FROG'S BLOOD. (Ranvier.) 



a, red corpuscle seen on the flat ; v, vacuoles in a cor- 

 puscle ; b, c, red corpuscles in profile ; k, n, pale cor- 

 puscles at rest ; m, pale corpuscle exhibiting amoe- 

 boid movements ; p, colourless fusiform corpuscle. 



it to swell into a globular form and then to become decolorised ; solu- 

 tion of salt causing wrinkling of the envelope, and so on. Boracic acid 

 acts like tannic acid in causing the haemoglobin to be withdrawn from 

 the envelope ; but it becomes partially or wholly collected around the 

 nucleus, which may then be extruded from the corpuscle. 



The colourless corpuscles (fig. 16, Jc, m, n), although larger, are very 

 similar to those of mammals. Like them, they are either wholly pale 

 or inclose a number of dark granules. They vary much in size and in 

 the activity of their amoeboid movements. They may have one or 

 several nuclei. Keagents have the same effect upon them as on those 

 of mammals. The presence of glycogen may be demonstrated in them 

 by its reaction with iodine (port-wine colour). 



