'74 
Notes on Recent Literature. 
The generalisation of Schimper and Meyer, that chromato- 
phores invariably arise from pre-existent chromatophores and thus 
persist throughout the plant’s life cycle and from generation to 
generation, has never been seriously called in question for certain 
Algae with large single chromatophores; and their further view that 
in all oogamous plants the chromatophores are carried by the 
female gamete alone has also obtained support and fairly general 
acceptance. In Spirogym, for instance, as shown by Chmielevsky 
(1890), the chromatophore of the male cell disappears at conjugation 
while that of the female cell divides and give rise to the chromato¬ 
phores of the new plant. Various writers, prior to Pensa and 
Lewitsky, have however considered that Schimper and Meyer’s 
generalisation may not apply to the higher plants, having failed to 
obtain evidence of the existence of plastids in the oosphere or the 
embryo of flowering plants. Almost simultaneously with the 
publication of Schimper’s and Meyer’s papers, Mikosch (1885) and 
Belzung (1887) stated that they could find no chromatophores in 
the resting seeds which they investigated. Mikosch examined not 
only seeds and seedlings but also the young leaves of various plants, 
and in all cases found that the chromatophores arose directly from 
the cytoplasm, probably by a process of condensation due to loss of 
water, the bodies thus formed being at first rod- or spindle-shaped 
but later assuming the typical discoid form of chloroplasts. Belzung 
investigated the ripening seeds, mature seeds and seedlings of a 
large number of plants and in his 1887 paper concluded that growth 
of starch grains can take place without the intervention of 
leucoplasts, that chloroplasts are formed directly by differentiation 
of the general cytoplasm, and that chloroplasts may also be formed at 
the expense of starch grains which have originated in the cytoplasm. 
Schimper’s criticism of his work led Belzung to make further 
investigations, the results of which he published in 1891 and which 
simply verified and extended his former conclusions, for he now 
stated that the young embryo has no chromatophores, that the 
starch grains formed in it are laid down in vacuoles of the cytoplasm, 
that the leucoplasts described by other observers are merely the 
boundaries of vacuoles in the cytoplasm, that the green colour of 
the embryo in many plants is due to chlorophyll distributed 
throughout the cytoplasm of the cell, and that chloroplasts are not 
formed until germination when the green pigment infiltrates into 
disintegrating compound starch grains and thus a chloroplast 
arises. Bredow (1890), Famintzin (1893) and more recently Miller 
(1911) have however stated that chloroplasts are present in resting 
seeds, though little appears to have been done in the way of testing 
the Schimper-Meyer theory that chromatophores are present in the 
oosphere and that these give rise to the whole of the chromato¬ 
phores of the plant—a theory, it may be said, for which the 
authors brought forward very insufficient evidence in the form of 
convincing data so far as the higher plants are concerned. 
In order to decide whether the Schimper-Meyer theory is of 
general application, it is necessary that the history of the chromato¬ 
phores should be traced throughout the whole life-cycle, and this 
has only been done in recent years, in the case of flowering plants, 
by the upholders of the Pensa-Lewitsky view, and in that of 
Bryophyta by Sapehin and by Scherrer. The two latter writers, as 
