789 
not constitute any criterion for the behaviour of some compound or 
other towards the living cell, because this coefficient of distribution 
need not have any relation to that of the same compound between 
this “lipoid” and water. The more so, where also the physical 
properties of fatty oils and “lipoids” are wide apart; the latter are 
e.g. lyopbile colloids, swell with water (with the exception of 
cholesterine, ete, which for this reason is considered by Lorwe ') 
to belong to a separate class of ‘‘semi-lipoids’’), and give accordingly 
rise to entirely different circumstances. Overton”) has also felt this 
difficulty, and has already adduced arguments for it himself (which 
are, however, still open to criticism and have in fact already been 
called in question); though the commercial salts of basic aniline 
dyestuffs are almost or entirely insoluble in olive oil, they easily 
dissolve in molten cholesterine or in cholesterine dissolved in oil, 
and also in lecithine *). I have been able to confirm this once more 
myself for a number of dyestuffs. 
5. There would not have been any reason for this criticism of 
the lipoid theory for it has been opposed by numerous investi- 
gators, and may be considered as pretty well refuted —, if not of 
late WarrrMaN‘*) had again explicitly expressed the parallelism 
between the coefficients of distribution lipoid components-water and 
olive oil-water, and had tried by comparison of the last-mentioned 
coefficients of distribution to give an explanation of the greater or 
less facility with which these compounds are assimilated by Penzci- 
lium glaucum. From what we have communicated above it may 
appear that the good results which WATERMAN is said to have 
obtained in this attempt, should be ascribed to accidental circum- 
stances, and that in any case no general significance may be assigned 
to them. This is also confirmed by our researches *) on the assimi- 
lation of unsaturated acids by Penicillium glaucum and Aspergiilus 
niger contained in our first communication; even on the assumption 
that the lipoid solubility of these acids is comparable to that in 
olive oil, an explanation of the behaviour of these substances with 
regard to moulds is by no means possible. 
Laboratory of the Dutch Commercial University. 
Rotterdam, August 19. 1920. 
1) Biochem. Zeitschr. 42, 217 (1912). 
3) Jahrb. f. wissensch. Botanik 34, 669 (1900). 
3) Loewe (loc. cit.) has later carefully studied the behaviour of ‘“‘lipoids’” and 
“semilipoids” with regard to dyestuffs (methylene blue) and derived forcible 
arguments against the OveRToN-MEyYER theory from his results. 
4) Proefschrift Delft (1913); Centralbl. f. Bakteriologie 42, 639 (1914) etc. 
5) VERKADE and SönNaeen; loc. cit. 
oi? 
