CENTROSOME AND SPHERE IN CELLS OF THE 

 OVARIAN STROMA OF MAMMALS. 



A PRELIMINARY COMMUNICATION. 

 C. M. CHILD. 



THE presence of centrosome and sphere in the cell has been 

 found in the majority of cases to present some relation to the 

 karyokinetic processes. The number of cases, however, which 

 appear to indicate that the function of the centrosome and 

 sphere may extend beyond their connection with karyokinesis 

 is being multiplied. 



Without making any attempt at completeness, a few of the 

 references bearing on this point may be given here. Heiden- 

 hain ('94) and Flemming ('91), among others, have studied the 

 centrosome in leucocytes and giant cells; Dehler ('95a) and 

 Lenhossek ('95b) have found them in ganglion cells of the frog; 

 Miss Lewis ('96c) has found them in ganglion cells of an anne- 

 lid, and they have been demonstrated in various tissue cells 

 besides ('91). 



In some of these cases it appears probable that the cells 

 under consideration have completed their karyokinetic history, 

 and that the centrosome is merely a relic of a past stage, or 

 else that it possesses some additional relation to the economy 

 of the cell which is not as yet understood. 



Again Morgan's ('96b) recent work on the production of 

 artificial astrospheres in sea-urchin eggs appears to indicate 

 that structures at least very similar to centrosomes and 

 spheres may appear as the result of abnormal environment. 

 Auerbach's ('96d) latest work on spermatogenesis shows the 

 formation of a " Nebenkern," which without doubt corresponds 

 to the sphere in this case in each generation of sperm cells. 

 After its appearance in the last generation at the close of cell- 

 division, the " Nebenkern " has a special function to fulfill in the 

 metamorphosis of this cell into the spermatozoon. These cases 



