220 MARCAKKT R. MTRRAY. 



consumed between the time when the first suggestion of a 

 droplet appeared on the outer surface of the external follicular 

 membrane, and the time when the exuding droplet became 

 perfectly spherical and separated itself from the membrane and 

 lay free in the culture medium. The fact that the droplets pass 

 out so readily indicates that the membrane is coarsely porous. 

 It should be added that the cultures observed for the movement 

 of the distal granules were uninfected and in good condition 

 otherwise, hence the activity recorded is presumably a typical 

 one, and not a result of fatty disintegration of the follicle cells. 

 Moreover, the number of distal droplets in the cells does not 

 tend to increase with the age of the culture, but rather to decrease. 

 This decrease is coincident with the gradual decrease in the 

 food and oxygen supply afforded by the medium. 



By means of fixation and of vital staining, a histo-chemical 

 identification of these cell inclusions is somewhat dubious. 

 There may, however, be some value in suggestions as to what 

 class of compounds the various inclusions belong. To this end 

 the Table of Chemical Constitution of Fatty Substances (by 

 Dr. W. Cramer in Lee's " Vademecum," page 358), Kingsbury 

 ('n), Bell ('14), Bowen ('19), Smith and Mair ('10), and other 

 works have been consulted with reference to the charts of the 

 color reactions of these inclusions. The constitution of the 

 medulla of the distal droplets seems to be something in the 

 nature of a true fat, mixed, or perhaps combined, with a little 

 protein, as suggested by the grayish base left after treatment 

 with solvents. All the reactions of the medulla except its ready 

 solution in turpentine after osmic acid fixation might be inter- 

 preted as the reactions of Golgi bodies. The latter, however, 

 relegates it to some other group of lipoids, as does its passage 

 into the haimocoel. The cortex reacts as a lipoid with the 

 lipoid fixatives, but is preserved through the alcohols after 

 treatment with Bouin's fluid. 



As to the function of the distal droplets in the life of the 

 organism, I have as yet little or no indication. It is possible to 

 conceive of them as an endocrine secretion from the follicle, 

 although this seems unlikely in the insects; or, they might be 

 merely excretory products. 



