CYTOLOGICAL CHANGES ACCOMPANYING DESICCATION. 339 



and the substance of the nucleolus has apparently diffused 

 throughout the nuclear area. 



The changes described for the drying corn cells in the last 

 paragraph are at first sight remarkably like those occurring in 

 the rotifer during desiccation. In both rotifer and corn the 

 nucleus contains a nucleolus surrounded by a clear space, 

 while around the two is a chromatic membrane of varying 

 thickness. When water is removed the clear space around the 

 nucleolus disappears and comes into existence again only upon 

 the addition of water. The substance of the nucleolus in both 

 cases diffuses toward the periphery of the nucleus leaving a more 

 or less clear space in the center of the same. In the cytoplasm 

 also there is a parallel between the behavior of the cells of the 

 two forms. Loss of water is attended by shrinkage and a conse- 

 quent increase in density. The cytoplasmic materials tend to 

 gather in small lumps which remain closely packed together until 

 moisture is again applied. 



Whether the seemingly similar processes in these representa- 

 tives of the plant and animal kingdom are indeed analogous can 

 be determined only after further study. 



LITERATURE CITED, 

 de Beauchamp, P. M. 



'09 Recherches sur les Rotiferes: les formations tegumentaires et 1'appareil 



digestif. Arch. Zool. Exp., Paris, Ser. 4, Vol. 10. 

 Jacobs, M. H. 



'09 The Effects of Desiccation on the Rotifer Philodina roseola. Jour. Exp. 



Zool., Vol. 6. 

 Janson, F. O. F. 



'93 Versuch einer Uebersicht liber die Rotatorien-Familie der Philodinaeen. 



Abh. der Nat. Ver. zu Bremen, Band XII. 

 Zelinka, C. 



'86 Studien iiber Raderthiere. Ueber die Symbiose und Anatomie von Rota- 

 toria aus dem Genus Callidina. Zeit. Wiss. Zool, Band. 44. 



