GLANDULAR CELLS OF THE FROG'S PANCREAS 363 



ance of the above hypothesis; since the two do not necessarily 

 exhibit the same reaction for various stains, and also we know 

 that secretion granules are assumed by many recent investigators 

 to be derived from the other constituent of the cell. This mat- 

 ter will be more particularly discussed when the genesis of zymo- 

 gen granules is considered. 



2. In more recent times, Hoven ('10), Prenant ('10), Champy 

 ('11), and Mislawsky ('13) identify the basal structures with 

 mitochondrial filaments, assuming that the former is a modifica- 

 tion of the latter artificially brought about by the fixation. But, 

 I cannot agree with this view; for these two structures may be 

 easily brought into view by staining in one and the same prepara- 

 tion, as aready described by Regaud and Mawas ('09), Arnold 

 ('10), and Bensley ('11); they also differ markedly from each 

 other not only in morphology and staining reactions, but also in 

 their biological significance. 



3. The view of Eberth and Muller ('92) and Bensley ('11) ap- 

 proaches that of my own. The former authors state that the 

 fibers and rods in question are products of the adhesion of pro- 

 toplasmic fibers; but how this change is brought about, in other 

 words, whether they are preexistent or postmortem structures, 

 cannot be seen in their description. On this point, Bensley ex- 

 presses himself more distinctly, maintaining that the basal fila- 

 ments are fixation artifacts produced by the precipitation effect 

 of acid. He says: " the real basal substance of the cells is homo- 

 geneous. It is quite possible, however, that the basal filaments are 

 preexistent in the living cell though invisible because they are 

 imbedded in a substance of the same refraction index, and that 

 they are rendered visible in the acid fixation by contraction." 

 There is, however, some difference of opinion between Bensley 

 and me ; he considering basal filaments as preexistent and ignoring 

 my protofibrillae. The basal filaments which we find in fixed 

 preparations I believe to be nothing but my protofibrillae to some 

 extent adherent into bundles. 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 26, NO. 3 



