Notes on Recent Literature. 
17 6 
deformed leucoplasts. While preparing this account of recent work 
on chondriosomes I was much struck by the remarkable outward 
resemblance between these bodies as described and figured by 
Meves, Lewitsky, Porenbacher and others, and the “myelin forms” 
described by Nestler and other writers on the biochemistry of 
lipoids and made a few simple experiments on lines suggested by 
the work of these writers. On adding ammonia to oleic acid or to 
olive oil (or on adding water, or various salt solutions, or albumin 
solution to lecithin), and watching the result on a slide under the 
microscope, there are formed, as stated by these writers, 1 peculiar 
and varied structures—rounded, rod-like (long or short and straight 
or hooked or spirally coiled), dumbbell-shaped, moniliform, etc.— 
which present the most striking correspondence in form with all 
the various types of chondriosomes that have been described and 
figured. Meanwhile there has appeared a paper by Lowschin (1913), 
who has gone into this matter in some detail, finding that the 
myelin forms obtained from lecithin resemble chondriosomes in 
various respects other than mere form—they can be “ fixed ” (see 
below) with chromic acid, osmic acid and formalin, but are destroyed 
by acetic acid. Myelin forms appear to have been first observed 
in 1886 by Virchow, who found that when nerve fibres are placed 
in water the axis cylinder swells and escapes as rounded, ovoid or 
elongated masses ; later it was found that similar bodies are formed 
when fatty acids or fats or bodies like lecithin are treated with 
emulsion-producing substances, and that they are simply emulsion 
forms. In size they vary considerably according to the mass of the 
material, the fineness of its division, and the chemical and physical 
characters of the medium ; their form depends on the composition 
of the bodies, their surface tension and the nature of the medium— 
for instance, elongated forms are produced when there is streaming 
in the medium. They show both transverse division and longitudinal 
splitting like that described for chondriosomes, and various changes 
are observed as they appear, develop and finally disappear—from 
homogeneous threads (chondriokonts) are developed granular threads 
(chondriomites) and these may break up into single granules (mito¬ 
chondria), while the latter in turn may become aggregated to form 
chains. They are very sensitive to various reagents, alkalis causing 
them to break up into granules, as is the case with chondriosomes. 
As Lowschin admits, these extraordinary resemblances between 
myelin forms and chondriosomes may be mere analogies of no 
special importance; in this connexion one must bear in mind the 
various types of “ amoebae ” obtained in foams and in other ways, 
Leduc’s “ artificial cells,” Burke’s “ radiobes,” etc. 
The analogy between myelin forms and chondriosomes apparently 
goes further than this, however, for according to Faurd-Premiet, 
who regards chondriosomes as consisting of an albuminoid or proto¬ 
plasmic ground-mass combined (either by ordinary chemical union 
or by adsorption) with a lipoid substance, the fixatives used in the 
study of chondriosomes (those based on chromic or osmic acids, etc.) 
render lipoids, or fatty substances in general, insoluble in fat-solvents 
such as those employed in cytological technique (xylol, alcohol, etc.), 
while fatty bodies thus “fixed” are stained in exactly the same way 
as chondriosomes by the staining methods regarded as specific for 
’ For descriptions of these myelin forms, see Molisch, “ Mikrochemie der 
Pflanzen,” 1913, pp. 109-111, and the literature cited by him. 
