NATORE 
361 
THURSDAY, FEBRUARY 18, 1904. 
MORPHOLOGY OF THE FLOWERING 
PLANTS. 
Morphology of Angiosperms. Part ii. Morphology of 
Spermatophytes. By J. M. Coulter and C. J. 
Chamberlain. Pp. x + 348; illustrated. (New 
York and London: Appleton and Co., 1903.) 
Dees the last decade or so the aspects of vege- 
table morphology have undergone an astonish- 
ing change, one indeed almost approaching the 
nature of a revolution. Many of the controversies of 
twenty years ago have now ceased to excite interest, 
and those old standing problems on which attention 
will always be concentrated have come to be regarded 
from other standpoints, whilst hosts of new ones have 
hustled themselves to the front. Several causes 
have contributed to effect this change in the whole 
perspective of the science. The introduction of more 
precise methods of observation and experiment has 
resulted in the disintegration of more than one 
cherished superstition, but it has been at the same time 
fertile in good results by leading to a re-examination of 
the foundations of our morphological beliefs. Our 
horizon has been greatly extended by the remarkable 
have been thus enabled to link together many facts 
and phenomena the connection of which had hitherto 
been unsuspected or at the best but guessed at. 
Sooner or later the newer points of view come to be 
reflected in new types of text-books. The volume be- 
fore us is one of these pioneer works. It makes no 
pretence of dealing with the whole range of so vast 
a subject as that of the morphology of angiosperms, 
but the authors have wisely selected, out of the mass 
of information at their disposal, such material as may 
illustrate the main thesis they had in view in writing 
the book. This thesis might perhaps be fitly described 
as the angiosperms from a phylogenetic standpoint. 
The whole treatment converges to this end, including 
also the somewhat curtailed account of angiospermic 
anatomy separately contributed by Prof. E. C. 
Jeffrey. 
Naturally the different portions of the work are of 
unequal value; this is partly to be attributed, as in 
the case of the later geological evidence, to the com- 
parative exiguity of trustworthy information, and in 
part also, perhaps, to considerations of space. 
The general character of the treatise may be 
gathered from the headings of the earlier chapters. 
Thus we find the microsporangium, the mega- 
sporangium, the female gametophyte, fertilisation, 
the endosperm, all receiving a full treatment in 
separate chapters. 
history of a typical angiosperm are similarly dealt 
with, and each phase is treated from a comparative 
standpoint. 
One of the most interesting discussions, at least to | 
an advanced student, is that on the phylogeny of the 
two main divisions of the angiosperms. 
probabilities are ably put forward and sifted, and after 
NO. 1790, VOL. 69] 
The various | 
reviewing the whole, the authors are inclined to con- 
sider the dicotyledons as having sprung from a stock , 
distinct from that which gave birth to the mono- 
cotyledons. They are inclined to regard the un- 
questioned similarity in the stages characteristic of the 
germination of the embryosac, in the two phyla re- 
spectively, as being attributable rather to convergence 
than to community of origin, much in the same way, 
perhaps, as we now recognise heterospory to have 
appeared independently in all the advanced groups of 
vascular cryptogams. But in this instance, as in 
others in which there is also room for great divergence 
of opinion, one cannot fail to be struck by the fairness 
with which they present the evidence, even when it 
militates against their own particular view. 
The angiosperms as a whole are likewise considered 
to have originated independently of the gymnosperms, 
in spite of the apparent points of contact exhibited, e.g. 
by the Gnetacez in certain of their reproductive struc- 
tures, with the higher group. The differences are held 
to be of such moment as to be irreconcilable with any 
close affinity, and the authors emphasise their position 
by proposing to retain the term spermaphyte as one 
| of mere convenience, and not as in any way implying 
near relationship. Probably many will agree with 
this attitude of caution in the absence of more 
| paleontological evidence than we at present possess, 
advances made in palzontology and cytology, and we 
and it is at any rate clear that modern work has’ 
sufficed to accentuate the remoteness of the gymno- 
sperms, not only from the dicotyledons with which 
they were formerly grouped, but from the whole angio- 
spermic class. 
It cannot, of course, be expected that all the theo- 
retical interpretations and conclusions advocated by 
the authors will commend themselves with equal force 
to other botanists, and we find ourselves unable to 
follow them in all their proposed modifications of 
terms. Thus it does not appear to be a substantial 
gain to limit, even implicitly, the term dioecious to the 
gametophyte. The word is perfectly well understood 
in connection with the sporophyte, and if we accept 
(as it seems reasonable to do) their own conclusion 
that the spore-mother cell is the point at which the 
sporophyte generation terminates, the term may still 
serve according to the current use. For if the game- 
tophyte is regarded as being inaugurated on the division 
of the spore-mother cell, the spores themselves, pro- 
duced within the tissues of the sporophyte, form an early 
stage of the sexual generation. This view is based on 
the important nuclear changes associated with the 
formation of the spores, and it has already been 
adopted, at least in this country, as a cardinal point 
in the life-history of the higher plants. The objection 
raised against the terms gynecium and andrcecium 
| by reason of their conveying a significance as to sex 
Other important phases in the life- | 
is quite parallel to the one before mentioned; but no 
one would regard the term male or female, as applied 
to an animal, to be incorrectly used on the ground 
that the sexual elements are the real male and female 
cells. The matter is not affected by the fact that these 
tissues are often segregated from the soma at so early 
a period, and with such definiteness, that many zoolo- 
| gists have concluded that there is a fundamental dis- 
R 
