Notes on Recent Literature. 
jo6 
anaphase move towards the poles so that each daughter cell 
receives an approximately equal number of chondriosomes which 
then again become arranged around the nucleus in close contact 
with its membrane. The filaments (chondriokonts) then undergo 
segmentation so as to form short rods, and as leaf development 
proceeds these swell up, become ovoid grains, and are eventually 
transformed into chloroplasts. In his later papers Guillermond 
found that chondriosomes occur in every cell of a flowering plant, 
whether vegetative or reproductive, so that they may be traced 
throughout the life cycle, being invariably formed by division of 
pre-existing chondriosomes derived in the first instance from the 
chondriosomes of the parent pollen-tube and oosphere—hence in 
this respect plant chondriosomes are homologous with those of 
animals; that they are therefore cytoplasmic structures sni generis ; 
and that they may either remain unaltered or may be transformed 
into leucoplasts or further into chloroplasts—and, conversely, that 
chromatophores (in flowering plants at any rate) are invariably 
formed by the growth and modification of chondriosomes. He 
found that leucoplasts were formed in somewhat different ways in 
different plants— e.g., as small swellings at various points on a 
chondriokont (seedling of Pisum, Zea, Ricinus, etc.), as large 
fusiform bodies arising from an entire chondriokont (Phajus tuber), 
by differentiation of the constituent granules of a chondriomite 
(Ranunculus Ficaria tuber), or by that of isolated mitochondria 
(potato tuber), and so on. In his work on the buds of adult plants 
he obtained the same results as in the case of seedlings, the 
formation of chloroplasts in the stem cortex and in the leaves 
derived from the meristem of the bud taking place exactly in the 
same manner as in the plumule of seedlings, while the chondriosomes 
of the stem stele persisted without change or were transformed 
into leucoplasts. As in the case of leucoplasts, the mitochondria 
swell up, the central portion becomes clear and but little stainable 
as compared with the peripheral portion, and eventually one or 
several starch grains appear in this central portion. 
In the longest of his later papers on this subject (Arch. d’Anat. 
Microsc., 1912, pp. 309-428) Guillermond summarises the work 
done by himself and others up to that time on the origin of plastids 
from chondriosomes, and points out that the morphological criterion 
—“ la differenciation morphologique des mitochondries,” that is, 
the origin of plastids “ d’un simple accroissement de volume de 
ces Elements ”—does not afford a sufficiently exact definition of 
chondriosomes; “ comme les mitochondries et les leucoplastes se 
colorent de la merne maniere, il est done extrtmement difficile 
d’ttablir line distinction entre ces deux formations.” Hence he 
attempts to define and distinguish these bodies on their micro¬ 
chemical characters, and from his results he concludes that while 
plastids show the same stain reactions as chondriosomes, the latter 
are usually soluble in alcohol and acetic acid while the former are 
not. He does not lay much stress upon the results obtained at 
present but remarks that much further microchemical work is 
required, and he concludes that “ mitochondries et leucoplastes 
sont done des formations apparenttes qui paraissent constitutes 
d’une substance tres voisine.” 
(to be continued). 
