18 H. HAY.S BULLARD 



that they are not strictly normal one should bear in mind that 

 they are not markedly pathological and in nearly all cases they 

 would soon return to the normal if over-feeding were discontinued. 

 Table 7 shows the results obtained by the examination of the 

 hearts of ten hogs, eight sheep and four oxen. The amount of 

 fat in the cardiac fibers of the ox and sheep appears to be on the 

 average somewhat greater than in hogs although the latter ani- 

 mals show more subcutaneous adipose tissue. Figure 9, at L 

 and D, shows a section of cardiac fibers from a hog (no. 104). 



Fetuses and suckling animals. Table 8 is intended to give an 

 idea of the amount of fat in the cardiac fibers during the later 

 stages of fetal life and in sucklings. In the majority of cases 

 shown in the table the quantity of fat is designated as moderate 

 and in no case is it entirely absent. Figure 7 represents a sec- 

 tion of muscle fibers from the apparently normal heart of an eight 

 months human fetus. 



Other animals. The heart muscle of several of each of the fol- 

 lowing species was examined; mouse, opossum, rabbit, guinea- 

 pig, monkey. In each of these animals a considerable quantity 

 of visible fat is normally present in the cardiac fibers. 



Human. Excepting in comparatively rare cases of sudden and 

 violent death, human hearts at autopsy are seldom to be consid- 

 ered strictly normal. In many cases death is preceded by a period 

 of inanition and as we have seen, this condition may be expected 

 to bring about the more or less complete disappearance of visible 

 fat from the cardiac fibers. In several human hearts, however, 

 which were normal in color and showed no cloudiness, opacity or 

 yellowish white appearance, a moderate amount of fat was 

 present in the typical diffuse general form found in the normal 

 hearts of animals. I believe that it will finally be shown beyond 

 doubt that microscopically visible fat is present in normal hu- 

 man cardiac muscle. This view is advocated by Bell (12) and 

 Wegehn ('13) each of whom has demonstrated visible fat in 

 apparently normal human hearts. There can be little doubt, 

 however, that the well known 'mottled fatty degeneration' is 

 pathological. 



