MUSEUM OF COMPARATIVE ZOOLOGY. 361 



curled filaments, which are continuous by means of central and periphe- 

 ral loops; that from the latter arises a meandering glomerule (Win- 

 dungsknauel) and from this a trestle with intermediary substance. Aside 

 from the double star this is the same series of forms assumed by the mother 

 nucleus, hut in reverse order. 



From a comparison of the whole series of changes Flemming presents 

 the following scheme as probably representing the double series of nu- 

 clear changes which accompany cell division in Salamandra, — the one 

 progressive and affecting the mother nucleus, the other regressive, and 

 (since it follows the division) pertaining to the daughter nuclei. 



Mother nucleus Daughter nuclei 



(progressive). (regressive). 



1. Trestle (quiescent). 1. Trestle (quiescent). 



i t 



2. Fine-thread glomerule. 2. Fine-thread glomerule. 



t 



3. Thickening of the fine threads and 3. Narrowing [of the coils]. 

 I loosening of the coils. \ 



4. Central and peripheral loops (crown 4. Central and peripheral loops (crown 

 I form). f form). 



(Rupture of the loops. ) (Union into loops ?) 



5. Star form of mother nucleus. 5. ^ Star form of daughter nuclei. 



I Coarse-rayed half-cask. 



6. Fission of its rays. 6. Fusion of rays in pairs (?). 



\ t 



7. Fine-rayed star. 7. Fine-rayed, half-cask. 



8. Equatorial plate. 



Results on other cells are mostly confirmatory of the changes given 

 above. However, in connective-tissue cells an incomplete division results 

 in a cell having two nuclei ; this is more rarely seen in epithelium. In 

 red blood-corpuscles the nuclear filaments so increase in extent as to reach 

 to near the periphery of the cell. The author thinks the cell substance 

 has in this case contributed to the remarkable increase in the bulk of 

 the nuclear figure, and finds an argument to support this view in the fact 

 that filaments of the nuclear figure in unstained chromic acid prepara- 

 tions have a peculiar greenish brown or brownish yellow color correspond- 

 ing to that of heeraoglobin. This, he adds, would be a striking confir- 

 mation of Auerbach's theory of the mingling of nuclear substance and 

 cell substance in division, were it not that the substance of blood-cells 

 is very peculiar as compared with that of other cells, and that in other 

 cells such a phenomenon does not take place. 



