672 INTERNAL SECRETIONS AND PRESERVATION OP LIFE. 



differing somewhat from the recognized "ingulfing" or "inglob- 

 ing" process through which phagocytes take up germs, small 

 particles, etc. An example of this mode of appropriating vari- 

 ous plasmatic or foreign substances is illustrated in Fig. 5, 

 which shows bacteria penetrating, from various directions, into 

 the cell-wall, while Fig. 16 shows the bncteria within the peri- 

 nuclear vacuole. As all the cells in Metclmikoff's plate are 

 phagocytes, the mechanism of ingestion to which we refer is 

 not only that of basophiles, but is obviously a feature of all 

 leucocytes. 



We must emphasize the fact that we say "perinuclear" 

 vacuole, and not "nuclear" vacuole, for, if this and the other 

 germ-laden cells just referred to are carefully examined, it will 

 become evident that the bacteria lie in a pocket contiguous to, 

 but not forming part of, the nucleus itself. We would not say, 

 therefore, with Bail, "vacuoles in the nucleus," but vacuoles 

 around the nucleus. Indeed, Gulland refers to Heidenhain as 

 considering that "the nucleus lies free in the interfilar spaces, 

 and is not organically connected with the cell-substance." This 

 is quite in accord with our view, and it seems to us that it 

 represents the cavity into which bodies ingested by leucocytes 

 normally arrive, though smaller vacuoles are likewise present 

 in the cytoplasm. 



The actual presence of this perineuclear vacuole from 

 which canaliculi would start appears to us indicated in several 

 of the figures in the annexed Gulland's plate. Fig. 8, for in- 

 stance, stained with iron-ha3matoxylin, shows that the nucleus 

 is surrounded by an irregular limiting material of some kind; 

 but if we compare the outline of this limiting substance with 

 that of all the succeeding cells, an interesting feature asserts 

 itself, viz.: its thickness is extremely variable. Although 12 

 may be said to be moderately regular, the others, in the fol- 

 lowing sequence: 11, 10, 13, 8, 9, and 14, are increasingly irreg- 

 ular. If now this irregularity itself is scrutinized, a significant 

 fact is revealed: i.e., the bulges, or projections, in the limiting 

 structure are all at the expense of the nucleus. In Fig. 9, for 

 instance, just above a clover-like figure near the center of the 

 cell (probably the astrophere), the marked bulging shows every 

 evidence of having been formed by a substance which had com- 



