88o 



THE AMERICAN NATURALIST. [V^ol. XXXVIII. 



to the very general rule, by amitosis. A renewed study of this 

 and kindred forms with reference to this point is much to be 



These cases of amitosis are sufficiently out of the common 

 order to require a turllior study in the light of the general prin- 

 ciples relating to the 

 -.. ,; ' amitosis question. That 



> ,: . / ' .r ^ j of the larval kidney could 



. perhaps be attributed to 



senescence but hardly to 

 metabolism, since cells 

 are found dividmg by 

 mitosis after secretory 

 activity has been going 



It is highly remark- 

 able that the t(H.d-ova nuclei should not divide mitotically, for 



divisi.Mis ot the nucleus ni ordinary eggs both in maturation and 

 ^e-incntation aic mitotic, and we are justified m expecting 

 karyokmesis ,,t tiie tood-ova nuclei. But instead their nuclei 

 are queer trom the first and seem to divkle amitotically. This 

 amitosis cannot be assigned to either senescence or metabolism, 

 the cells show no signs of secretory activity, and are not senes- 

 cent. The case of Spirogyra, according to Pfefter, and of the 

 salamander, according to Meves, are somewhat analogous in that 



