HIBERNATION IN THE POTATO BEETLE. 



393 



it intergrades with ordinary adipose tissue and under favorable 

 conditions is transformed into it." 



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FIG. 5. Upper left. Section of the fat body or adipose tissue of potato beetle 

 before hibernation. Note the numerous fat vacuoles partly masking the large 

 nucleus located centrally within the cell, and the minute granules dispersed among 

 the vacuoles. Flemming fixation, stained with hematoxylin. Photographed with 

 achromat 2 mm., lens, 1.3 numerical aperture with 12 X compensating eyfe piece. 



FIG. 6. Upper right. Section of the fat body after one month of hibernation, 

 showing the decreased size of the fat vacuoles and nucleus, the large and prominent 

 albuminoid granules grouped along the periphery of the cell exhibiting open spaces. 

 Staining and enlargement as in Fig. 5. 



FIG. 7. Section of the fat body after five months hibernation, showing the 

 almost complete absence of fat vacuoles. The prominently large albuminoid 

 granules are grouped in masses, the absence of cell outline of the fat body and the 

 almost entire disintegration of the nucleus. Staining and enlargement as in Fig. 5. 



