MITOCHONDRIA 



129 



intestinal fat-absorbing cells. A perusal of the very considerable 

 amount of work carried out by Ludford (23, 24, 77-81) will show 

 that although the actual amount of our knowledge of the behaviour 

 of these cell organs is increasing enormously, it is still practically 

 impossible to correlate the various phenomena satisfactorily. 

 Horning, however, claims to have found that the zymogen grains 



Fig. 60. — Cells from the thyroid gland showing the differences in form of the 

 Golgi apparatus and mitochondria in resting and active phases (from 

 Cramer and Ludford (24) ). A and B, Resting glands from animals 

 fed \vith thyroid or exposed to heat. C and D, Active gland from 

 animals given tetrahydronaphthylamin or exposed to cold. G., Golgi 

 apparatus ; L., lumen ; M., mitochondria ; iV., nucleus; w., nucleolus; 

 Sec.gr., secretory granules. 



of the pancreatic cells in the guinea-pig are formed from the fila- 

 mentous mitochondria (58). 



In the case of specialised cells, such as the male germ cells, the 

 position appears to be even more confusing. In the spermato- 

 gonium and spermatocyte they are present as filaments or granules 

 (Figs. 63, A, 64, A). During the spermatocyte divisions they do not 

 appear to separate into two subequal groups, but remaining near 

 the spindle in the centre of the dividing cell, become mechanically 

 cut into two groups by the developing cell wall (Figs. 63, C, 64, C) 



K.A..M. 5 



