GLANDULAR EPITHELIUM AND DIVISION OF NUCLEI. 415 



dyaster represents a more or less elliptical body, at the poles 

 of which the fibrils are connected into a network ; they 

 pass from one pole to the other as isolated longitudinal 

 fibrils. "We have a form that coincides with the spindle of 

 Strasburger, but in which the fibrils form a network at the 

 poles. Flemming has figured them very beautifully on his 

 Plates XVI and XVII. 



The axis, i. e. the line joining the poles of any " dyaster/' 

 lies in most instances parallel with the surface of the epi- 

 dermis, and only in few instances have I seen it more or 

 less vertical. This is, in so far, of interest, as it proves 

 that in many instances the two daughter nuclei (derived 

 from the division of the dyaster), and, consequently, 

 also, the two daughter cells, do not lie above one another 

 in a line vertical to the surface of the epidermis, but side 

 hy side. 



Then we find that the dyaster divides into two small 

 separate monasters, the longitudinal fibrils running from 

 one pole to the other of the dyaster dividing in the middle 

 one by one. We have finally two small nuclei side by side, 

 but separate, the fibrils of each possessing the arrangement 

 of a monaster. 



I find, just like Flemming, who so exhaustively described 

 them, that these daughter nuclei undergo the same changes as 

 the mother nuclei did, but in a reverse order, viz. passing from 

 the state of monaster into that of a " rosette " or " wreath," 

 from this into that of a " basket '' or '' convolution," and, 

 finally, into a nucleus containing a uniform spongy reti- 

 culum. While the daughter nuclei undergo these changes, 

 except the last, they are easily distinguishable from similar 

 forms of mother nuclei, owing to the smallness of the 

 former and their positions in couples (see figs. 22 — 25, PI. 

 XVIII). 



Justasis the case withmother nuclei in the stages of rosette, 

 wreath, and monaster, so also the daughter nuclei of the ana- 

 logous forms do not possess any membrane; in the "con- 

 volution " and " basket " of daughter nuclei the membrane is 

 very indistinct, and is also here due to the close position of 

 the fibrils. 



As has been mentioned above, the majority of daughter 

 nuclei lie at first side by side, i. e. in an axis parallel to the 

 surface. But after the cell substance itself has become 

 divided, the daughter nuclei gradually change their relative 

 position, the (imaginary) axis joining them, rotating so as 

 to assume a position vertical to the surface of the epidermis. 



The daughter nuclei enclosed in a still undivided cell 



