126 INANITION AND MALNUTRITION 



'89, '89a), Bizzozero and Torre ('81) and Denys ('87) in birds, and by Herter 

 ('98) in the pig. According to L. Neumann ('82), this description applies only 

 to chronic inanition; in acute inanition the cells do not become stellate. Geel- 

 muyden ('86) found gelatinous marrow in the bones of frogs after the winter 

 fast, and cited numerous observations on the same in human long bones in 

 diseases with emaciation (cf. Dickson '08). A review of the literature, with 

 description of the histological changes in the bone marrow of rabbits and pigeons 

 during inanition and refeeding was given by Jackson ('04). He concluded that: 



"Beim hungernden Thier ensteht Gallertmark, indem das Fett verschwindet, 

 und die Zellen ihre urspriingliche Reticulumform wieder annehmen. Die 

 Reticulumfasern liegen dann meistentheils zwischen den Zellen in der reich- 

 lichen gallertigen Grundsubstanz, thielweise aber auch innerhalb der Zellen oder 

 unmittelbar neben ihnen" (cf. Figs. 50 and 51). 



During hibernation the changes in adipose tissue have received much atten- 

 tion, since it has been shown that during hibernation the organism subsists 

 chiefly at the expense of its stored fat. Valentin ('57) found that in a marmot 

 hibernating 44 days, with loss of 8 per cent in body weight, the ordinary adi- 

 pose tissue had lost 19 per cent and the "hibernating gland" (" Winterschlaf- 

 driise") 27 per cent. In 3 other marmots at the end of hibernation (average 

 166 days), with loss of 35 per cent in body weight, the ordinary adipose tissue 

 had lost 99 per cent and the "hibernating gland" 68 per cent. Valentin ('58), 

 Afanassiew ('77), Ehrmann ('83), Carlier ('03), Hansemann ('02) and others 

 have shown that the so-called "hibernating gland" is composed essentially of 

 adipose tissue, whose cells during hibernation undergo simple or serous atrophy 

 similar to that found in adipose tissue in general during inanition. 



The subject of adipose involution during inanition was exhaustively investi- 

 gated by Hammar ('95) who described in the albino rat two types of fat, white 

 and brown. The "white fat" corresponds to the usual description of adipose 

 tissue; during inanition it is reduced to remnants of fibrous connective tissue 

 (never gelatinous) in the subcutaneous, subserous and intermuscular localities. 

 The "brown fat," which corresponds in general to what has been described as the 

 "hibernating gland" in many animals, has a different structure, each cell con- 

 taining a spheroidal nucleus and numerous fat droplets of variable size. Dur- 

 ing inanition the decrease in the weight of the "brown fat" is much less marked 

 than that of the "white fat," and its structural involution is also different. 

 It remains lobular in form, the color becoming dark reddish brown from blood- 

 vascular congestion. The fat cells are reduced in size, and form a syncytium 

 filling the intervascular spaces. The fat droplets are decreased in size and 

 number, or completely absent. The cytoplasm usually becomes coarsely 

 ganular, sometimes vacuolated, the nuclei unchanged. Apparently the cells 

 may undergo either simple or serous atrophy. Hammar's results were in general 

 confirmed by Auerbach ('02) for various species of rodents and insectivora, 

 including hibernating and non-hibernating forms, and by Rasmussen ('22, '23) 

 in the American woodchuck (Marmota monax rufescens). Changes in the 

 hibernating gland of the woodchuck appear slower than in other species; but 

 subsequent to hibernation and before food is plentiful it decreases rapidly 



