60 WARO NAKAHARA 



and that the normal gland cell, which must naturally be loaded 

 preparatory to discharging, contains no 'secretion material.' 

 These together with the fact that the vacuoles contain no stain- 

 able material seem to make Gilson's opinion untenable. 



According to Maziarski's ('11) observations, at the height 

 of the secretory activity of the cell, the nucleolar material is 

 discharged from the nucleus, not only as separate bodies^ but 

 also as accumulations in vacuoles in the form of droplets of 

 'prosecret,' being dissolved within the nucleus. I have gone 

 over my slides with special attention to this point, but the result 

 was negative. The appearances shown in his figures 13 to 27 

 do not occur in any of my slides, except those that apparently 

 show artificial conditions. I am, therefore, rather doubtful as 

 to whether the conditions observed by Maziarski, which led him 

 to conclude that on certain occasions the nucleoli become dis- 

 solved within the nucleus, and carried by vacuoles to the cell- 

 body, were normal. Even if they be normal conditions, we 

 should think that they indicate phenomena that occur very 

 rarely. 



The granules of migrated nucleoli appear to be somewhat 

 reduced in number, and some of them begin to show more or 

 less elongated masses at this stage. These granules may natur- 

 ally be supposed to hav6 something to do with the secretion of 

 the cell, since Gilson's ' vacuole-therory' is to be discarded, and 

 as far as my observations go, there are no other special granules 

 to be detected in the cell-body. Maziarski ('11) claims that 

 basophile granules, which he interprets as derived from chro- 

 matin, are also present in the cytoplasm. I have observed such 

 granules only in the degenerating glands obtained from prepupae! 



Maziarski ('11) considers the migrated nucleoli as the source 

 of the secretion of the cell, because these and the silk materials 

 in the lumen of the gland show similar color reaction. The fact 

 of the increase in their amount preparatory to the discharging 

 of the cell and its reduction as the cell discharges, also suggest 

 that the granules derived from the nucleoli may be the material 

 source of the silk-secretion. 



