THE CELL DOCTRINE. 123 



as peculiar forms in the development and division of 

 nuclei. 



Eimer* found in numerous nuclei that the gran- 

 ules of the " granular zone " surrounding his " hya- 

 loid " are due to protoplasmic filaments, which per- 

 meate the interior of the nucleus, and anastomose 

 with each other so as to form a network, which ex- 

 tends to the membrane of the nucleus, and also sends 

 radiating fibrils through the hyaloid into the nu- 

 cleus. The network of fibrils of the nucleus is, in 

 some instances, also in connection with fibrils and 

 networks of the same belonging to the cell substance 

 itself. 



The most recent contribution on this subject is the 

 valuable paper by Dr. E. Klein, already' alluded to, 

 and published in the Quarterly Journal of Microscopical 

 Science, for July, 1878. In this paper Klein shows 

 by observationsf on the ordinary freshly killed newt 



* Weitere Nachrichten uber den Bau des Zellkerns, etc., Archiv 

 f. Mikrostf. Anat., Bd. xiv, 1877, p. 94. Also, " JSotes and Mem- 

 oranda" of the April number of the Quart. Jour. Microso. Sci., ' 

 1878. 



j- The following is the method pursued by Klein : The stomach 

 of a freshly killed newt is cut open and placed Into a 5 per cent, 

 solution of chromate of ammonia in a closed vessel, where it is kept 

 for about twenty-four hours. It is then washed in water for about 

 half an hour, and placed after this in a dilute solution of piero- 

 carmine, where it is left till it assumes a deep pinkish-yellow tint. 

 It is now washed in water, and microscopic specimens are pre- 

 pared in this manner. The mucous surface of the organ is scraped 

 with a small scalpel, iwhereby smaller or larger flakes may be easily 

 removed ; they are placed in a very tiny droplet of glycerin on a 

 glass slide ; by slight knocking with the rounded or flat top of any 

 thin rod or needle-holder these flakes are broken up into micro- 



