Chondriosomes (Mitochondria) and their Significance. 171 
Schmidt (1912) published a general review of work on plant 
chondriosomes up to November, 1911, which he supplemented by a 
further review (1912) including 1911 and 1912 papers by Lewitsky, 
Forenbacher and Guillermond. In the general (Progr. rei bot.) 
review—useful, though incomplete and somewhat misleading—he 
showed strong bias in favour of the Schimper-Meyer theory and 
entirely overlooked a considerable body of work done during recent 
years which has either thrown considerable doubt upon the 
universal application of that theory or has altogether disproved it 
in the case of flowering plants at any rate (see general discussion 
later on the origin of chromatophores). In the second review he 
somewhat distorts Guillermond’s views, and attempts to turn the 
table upon the advocates of the view that chromatophores arise 
from chrondriosomes, by stating that the work of Lewitsky, Pensa, 
Forenbacher and Guillermond simply confirms the Schimper-Meyer 
view—according to Schmidt, these workers were merely dealing 
with the very early stages in the development of plastids which 
their technique enabled them to observe and which the simpler 
methods used by Schimper and Meyer were inadequate to demon¬ 
strate. According to Schmidt there are three possible interpre¬ 
tations of the nature of plant chondriosomes : these bodies are 
either (1) chromidia corresponding to those of animals, that is, 
portions of chromatic material derived from the nucleus, or (2) 
chromatophores in early stages of growth, or (3) special cytoplasmic 
structures. With regard to the first, he points out that very few 
botanists support the view that plant chondriosomes are actually 
extruded nuclear chromatin bodies, and that this view can only be 
accepted when confirmed by observations on living material; as to 
the second, that chromatophores in all stages of development give 
the same staining reactions as those considered characteristic for 
chondriosomes, and that (as stated above) in his opinion the new 
workers have simply brought valuable support to the Schimper- 
Meyer view ; while he denies altogether the probability or possibility 
of the third view. However, for the greater part, Schmidt’s 
criticisms are practically repetitions of those made by Meyer and 
referred to above, but though he appears to do less than justice to 
Lewitsky’s careful investigations it must be admitted that there is, 
as he points out, much room for further work on this subject and 
on that of plant chondriosomes generally. 
Rudolph (1912) published the results of his investigations in 
which he used the same plant (Asparagus officinalis) as that on 
which Lewitsky’s earlier work was mainly done. His object was 
to ascertain the relation of chloroplasts to chondriosomes, and he 
examined only the shoot-tip. On the whole his observations 
agree with those of Lewitsky as regards the chondriosomes 
themselves, but he could find no evidence of any relation between 
these bodies and the chloroplasts, and indeed he ends his paper 
with the remark that the single established fact resulting from all 
the work hitherto done on plant chondriosomes is that of the 
existence of such bodies in a large number of plants belonging to 
various groups. He found that in the youngest meristem cells the 
only chondriosome-like bodies present were granular, and that 
filamentous forms made their appearance later and were evidently 
produced by elongation of the granules prior to their division. 
