Notes on Recent Literature. 
227 
typically not formed by Sphagnum. The brief description of Ash- 
forest on p. 335 should certainly have been supplemented by a 
reference to the Ash-forest on limestone described by Moss in his 
“ Geographical Distribution of Vegetation in Somerset.” The 
citation of this paper in the bibliography (p. 392) is not quite 
accurate. 
The addition of the initial “o” to the word “ecology” we 
cannot but regard as savouring of a curious pedantry. The initial 
“ o ” has long been dropped in the English language in the case of 
the word “ economy,” and the obvious course seems to be to spell 
“ ecology ” on the same model, as is always done in America. It is 
difficult to know how such an artificial archaism can be defended. 
The general “get-up” of the book is good, and it is light in 
weight, while the price is satisfactorily moderate. 
A.G.T. 
NOTES ON RECENT LITERATURE. 
PROFESSOR STRASBURGER ON GENERAL 
CYTOLOGICAL PROBLEMS. 1 
After an intermission of eight years a new part of Professor 
Strasburger’s “ Histologische Beitrage” now appears. The author 
explains in his preface that, as editor of the Jahrbucher fur wissen- 
schaftliche Botanik, his botanical contributions naturally appeared 
in that journal; the considerable length, however, of the present 
work demanded separate publication. As a variety of cytological 
problems are dealt with which are exciting keen interest at the 
present time, and as the gist of the author’s views is not easily 
obtainable, owing the absence of “ General Conclusions,” it would 
seem useful to give a fairly full account of the author’s observations 
and critical discussions. 
The first matter dealt with is the interesting question of the 
determination of sex in the Bryophyta. The appearance in 1906 of 
the observation of Blakeslee (who showed that the spores of 
one and the same sporangium exhibited sexual differences) led 
Strasburger to the idea that the Liverworts might be suitable 
objects for the study of the question as to whether sex-segregation 
takes place at the division of the spore-mother-cells. In Spliczro- 
carpus terrestris, which had been studied earlier by Strasburger in 
connexion with the growth of the cell-wall, we have an admirable 
object, as the four cells of the tetrad remain united within a 
common exine and germinate in a readily distinguishable group. 
Further, the young plants produce their sexual organs so early that 
these can be recognised in plants only 0T mm. in diameter. An 
examination of material sent from Chartres confirmed Strasburger 
in his view, but the material was insufficient. Later, however, at 
the request of the author, Professor Douin examined material of 
1 E. Strasburger. Zeitpunkt der Bestimmung des Geschlechts, 
Apogamie, Parthenogenesis und Reduktions teilung. Histo¬ 
logische Beitrage, Heft VII., 1909, S.XVI, 120, 3 Tafeln. 
Fischer, Jena, M. 650. 
