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TEXT-BOOK OF PHYSIOLOGY. 



puscles of man and those of the domesticated animals, with the ex- 

 ception, perhaps, of the guinea-pig. The diagnosis of the 'corpuscles 

 of dried blood which have been altered by the action of various ex- 

 ternal agents, even though capable of a certain degree of 'restoration, 

 is most difficult, and should not be attempted in criminal cases with- 

 out large experience in microscopy, in measurements and methods 

 of preparation of all kinds of blood-corpuscles, and a proper per- 

 ception of corpuscular forms and sizes. In the following table the 

 average results of the measurements of the corpuscles in different 

 classes of animals are given (abstracted from Formad's compilation) : 



In birds, reptiles, and amphibians the corpuscles are larger 

 than in mammals, are oval in shape, and 

 nucleated. (See Fig. 100.) As the scale of 

 animal life is descended the corpuscles in- 

 crease in size, until in the proteus and am- 

 phiuma the long diameter attains an average 

 length of 0.058 mm. and 0.077 mm. respec- 

 tively. In fish the corpuscles are smaller, oval, 

 and nucleated, with the exception of the lam- 

 prey eels, in which they are circular, biconcave, 

 and nucleated, though the nucleus is gener- 

 ally concealed in the peripheral portion of 

 the corpuscle. As they are almost twice the 

 size of the human red corpuscles, they can, 

 notwithstanding the similarity of shape, be 

 readily distinguished from them. 

 Function of the Red Corpuscles. The red corpuscles, in 

 virtue of the capacity of their contained hemoglobin for oxygen 

 absorption, may be regarded * n tf ~ Tfr ~ ftv^n ^ i, in yg to 

 and therefore important factors in the generaTrespiratory 



FIG. ioo. AMPHIBIAN 

 COLORED BLOOD- 

 CORPUSCLES, i. On 

 the flat; 2, on edge. 

 (Landois and Stir- 

 ling.) 



* Masson. 



t Woodward. 



