FUNCTIONAL ACTIVITIES OF THE NUCLEUS 197 



of salivary glands when at rest and after stimulation. In more 

 recent years we have had the striking observation of Hodge, 

 confirmed by Gustav Mann, Lugaro, and others, upon the nuclear 

 alterations in the motor ganglion cells of bees, birds, cats, and 

 other vertebrates brought about by natural and experimentally 

 produced fatigue. 



These observations also clearly demonstrate that the nucleus 

 is not merely the vegetative centre of the cell, but is involved in its 

 functional activities. 



3. Finer Changes occurring in the Nucleus during 

 the Course op Cell Activities 



If I am not mistaken it was a native of what we regard as 

 the youngest of the civilized great countries of the world — 

 Professor Ogata — who first, in 1883, clearly recognized the 

 finer nuclear changes associated with secretory activity. He 

 called attention to the granules, or plasmosomes, appearing in 

 the nucleus at the beginning of secretory activity — granules 

 which take on the characters of nucleoli, and pass from the 

 nucleus into the cell body. In these he held that the zymogen 

 granules are developed which eventually become (part of) the 

 protoplasm of the cell. In 1887 Lukjanow made confirmatory 

 observations. He noticed in the secreting cell outside the 

 nucleus the agglomeration of little spherules which in form, size, 

 and reaction to dyes were closely related to certain nuclear 

 bodies (Kernkorperchen). He drew the cautious conclusion 

 that " it appears in any case that the hypothesis of a connexion 

 between the nucleus and the cell body has in itself nothing 

 improbable — a connexion shown outwardly by certain structural 

 elements of the nucleus passing over into the cell body, and 

 there undergoing further change." In the following year F. 

 Hermann noted the apparent discharge of similar minute globules 

 in mucous goblet cells during secretion, and also called attention 

 to the fact that these in staining powers resemble the nucleolus. 

 These he found were absent from the resting cell. In 1890 

 Professor Macallum made his first report upon similar phenomena. 

 He pointed out that in the nuclei of developing ova of Necturus 

 (the lake lizard, found here in Lake Ontario), as also in that of 

 the frog, at one stage the chromatin is principally collected in 



