386 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
of Kurt Muller,* who, after experimenting on over 300 rats, the pedigree 
of which had been carefully ascertained, failed to discover that the 
resistance of rats to anthrax was in any way due to the action of phago- 
cytes. The leucocytes, according to Muller, have no more to do with 
this resistance than many other elements of the tissues, and if they do, it 
is only as cells secreting bactericidal substances. This deduction was 
drawn from the observation that the degenerated bacteria were always 
found outside the cells and not within, though they may be seen in 
vacuoles of the hepatic tissue. M. Metschnikoff points out that as long 
ago as 1890 he demonstrated these vacuoles to be vacuoles in the macro- 
phages, and a common phenomenon in the spleen and liver of rats dead 
of anthrax. Muller has overlooked the existence of the macrophage, and 
has made a phagocyte the equivalent of a leucocyte, and hence his 
position is untenable. The author then replies to Mr. E. H. Hankin 
who advocates the theory of alexocytes.j The alexocytes are the eosino- 
philous leucocytes, and the granules the source of the bactericidal pro- 
perty of the blood. Hankin has lately withdrawn ( vide ante , p. 243) the 
word eosinophilous, substituting amphophilous for it. Of this alteration 
the author takes no notice, though he raises three principal objections to 
Mr. Hankin’s scheme. The first is that the bactericidal property as 
observed in a medium devoid of eosinophilous granules is thoroughly 
maintained. The second is that bacteria are incorporated by living 
phagocytes and are not previously killed by the action of “ alexines.” 
The third is the fact that the phenomena of phagocytosis and of intra- 
cellular digestion can be observed in Invertebrata which do not possess 
eosinophilous granules. In addition to these objections the author points 
out that Mr. Hankin has not yet proved that the eosinophilous granules 
are secretion products, and expresses the opinion that these granules 
represent a nutritive deposit heaped up in the phagocytes, and are 
analogous to vitelline granules and aleurone grains, all three being 
coloured alike by eosin. 
In conclusion, the author criticizes the statements of Messrs. Kant- 
hack and Hardy, whose experiments on the frog with anthrax are put 
forward by Hankin in favour of his views. The deductions of those 
writers are dismissed by M. E. Metschnikoff on the ground that the 
observations are imperfect and the conclusions erroneous ; they remarked 
that the eosinophilous cells approached the bacteria before the phago- 
cytes proper did. The two kinds of cells afterwards fused into pla modes 
and then destroyed the bacteria previously rendered harmless by the 
granules.* The author has no hesitation about saying that the phe- 
nomena thus described have no foundation in fact, and therefore it is 
impossible for Hankin to sui^port his theory of alexocytes from the 
observations recorded by Messrs. Kanthack and Hardy. 
New Bacterium of the Lymph.§— Dr. H. J. Hamburger describes, 
under the name Bacterium lymphagogon , a new microbe whose presence 
quickens the lymph-stream, and produces, by altering the osmotic con- 
* Cf. ante , p. 246. f Cf. this Journal, 1893, p. 515. 
X Cf. this Journal, 1893, p. 158. 
§ Verh. K. Akad. Wetenschap Amsterdam, iii. 5 (1893) 27 pp. 
