1918 Pomona College Journal of Entomology and Zoology, Vol. X, No. 2, June 



Connections Between Nucleus 

 and Cytoplasm 



WILLIAM A. HILTON 



While looking over some serial sections of a parasitic isopod, Grapsicephon of 

 the Family Bopyridae, I was struck with the appearances which some of the glan- 

 dular cells presented. Clear connections of nucleus and cytoplasm were found which 

 resembled very closely the conditions described by Stauffacher '10, and Knoll '10. 



These gland cells are among the largest of the parasite's body and the only ones 

 which presented this appearance. Not all of these gland cells looked alike.. There 

 were some that had a rather homogeneous appearance in the cytoplasm and even 

 less detail in the nucleus. The cytoplasm of these gave an acid reaction. Many 

 of the cells showed a decided reticulum which seemed to make up the framework of 

 both nucleus and cytoplasm, or at least this reticulum penetrated into the nucleus. 

 The chromatin granules are not very abundant in the nuclei of these cells, but in a 

 number of places chromatin is found in the cytoplasm attached to the reticulum. 

 Passing from the nucleus to the cytoplasm, or it may be from cytoplasm to nucleus, 

 are granules or masses of basichromatin. In many places these show partly in the 

 nucleus, partly in the cytoplasm. In almost every case the chromatin granlues seemed 

 to follow the lines of the reticulum in their migrations. 



The figures of Danchakoff '16, appear much like these preparations in places 

 and like the figures of Stauffacher. In the specimens of the former the chromatin 

 is migrating from the cell body to the nucleus. As these gland cells are apparently 

 differentiating for purposes of secretion and not for mytosis it seems probable that 

 the chromatin is leaving the nucleus. 



REFERENCES 



Daneliakoff, I' era 1916 



Studies on cell differentiation. Jour, morph. vol 27, No. 3. 



Knoll, W. 1910 



Betehen direkte, mit unseren heutigen Hilfsmitteln darstellbare Verbindungen 

 zwischen Kern und Cytoplasma? Zeit. wiss. zcol. xcv Bd. 1. Heft. 



Stauffacher, llch. 1910 



Beitrage zur Kenntnis der Kernstrukturen. Zeit. wiss. zool. xcv Bd. 1. Heft. 



(Contribution from the Zoological Department of Pomona College) 



