164 ANIMAL PHYSIOLOGY. 
of conditions has been too great. Deficiency in the quantity of 
the blood as a whole (oligemia) causes serious change in the 
functions of the body; but that a hemorrhage of considerable 
extent can be so quickly recovered from by many persons, 
speaks much for the recuperative power of the blood-forming 
tissues. Various kinds of disturbances in these blood-forming 
organs result in either deficiency or excess of the blood-cells, 
and in some cases the appearance of unusual forms of corpuscles. 
Anemia may arise from a deficiency either in the numbers 
or the quality of the red cells; they may be too few, deficient 
Fia. 157. 
Fie. 158.—Outlines of red corpuscles in a case of profound anemia. 1, 1, normal corpuscles ; 
2, large red corpuscle—megalocyte ; 3, 38, very irregular forms—poikilocytes ; 4, very 
small, deep-red corpuscles—microcytes, é : ‘ 
Fia. 154.—Origin of microcytes from red corpuscles by process of budding and fission. Speci- 
men from red marrow. ; ; 
Fie, 155.—Nucleated red blood-corpuscles from blood in case of leukeemia. 
Fig. 156.—Corpuscles containing red blood-corpuscles. 1, from blood of child at term ; 2, from 
blood of a leukemic patient. he 
Fie. 157.—a, 1, 2, 3, spleen-cells containing red blood-corpuscles. b, from marrow ; 1, cell con- 
taining nine red corpuscles ; 2, cell with reddish granular pigment ; 3, fusiform cell con- 
taining a single red corpuscle. c, connective-tissue corpuscle from subcutaneous tissue of 
young rat, showing the intracellular development of red blood-corpuscles. (Figs. 153-157, 
after Osler.) 
in size, or lacking in the normal quantity of hemoglobin. In 
one form (pernicious anemia), which often proves fatal, a 
variety of forms of the red blood-cells may appear in the blood- 
stream ; some may be very small, some larger than usual, others 
