3io 



à. ISHIKAWA. 



are the centrosouie.s so commonly observed ut the poles of the spindle 

 of the dividing nuclei of other animals. The ])ody now in question 

 is seen in Figs. 35, 31), 45, 49, 50, 51, (c). In Fig. 39 it is very 

 plainly visible in the centre of the upper archoplasm as a small round 

 body surrounded by a clear space. In the Ljwer archoplasm of the 

 same figure, it can not be seen so well, owing to its position beneath 

 the nucleus, but is discernible by focussing the tiil)e. In Fig, 44 two 

 centrosomes are seen close together in the centre of the archoplasm. 

 The nucleus to which this archoplasm belongs is, as stated above, in 

 the condition just before division, \vhile in Fig. 45 it is again seen as 

 a single body. It is also seen in four cells in Fig. 49, as small dark- 

 staining dots. This is also the case in Fig. 50, and in the arclio- 

 plasm on the left hand side of Fig. 52. It is not visible in other 

 figures, wliile in the archoplasm represented by Fig. 42 and more 

 clearly by Fig. 48, there is seen a number of small bodies in place 

 of the centrosomes. These bodies are not always quite spherical like 

 the ordinary centrosomes, many of them being more or less elong- 

 ated, and often presenting curved rods like those, described by Her- 

 niiuin (20, J). 585), in the spermatocyte of Proteu s ; tliey are perhaps to 

 be looked upon as a group of centrosomes like those, described by M. 

 Heidenhein (16, p. 54-()8), in the lymphocytes of rabbits. In my 

 [)revious paper I have given a case where tlie pr<jbable origin of the 

 centrosome from the nucleus is shown. Since then I have met with 

 no case similar to that one, but in another, I saw, at the side of a nu- 

 cleus whi(,*h had just divided, a sm:dl deeply stained body (c), close to 

 the nuclear wall, (Fig. 38) probably representing the last stage of the 

 disappearance of the centrosome within the nucleus. 



