March 2, 1894. 
Darwin; in the stem of Clematis vitalba; and in the petals 
of the artichoke. Aatsplitting enzymes have been dis- 
covered in seeds of Ricinus, rape, opium-poppy, hemp, 
flax and maize. In the castor bean it is distributed 
throughout the whole endosperm. 
These ferments seem to arise from vegetable zymogens, 
the existence of which was first established by Vines in 
experiments on Nepenthes. The constitution of en- 
zymes is still in dispute. Loew, as the result of 
analyses, considered them to be proteids closely allied to 
the peptones, but spectrum analysis and other evidence 
has now made this doubtful. Vegetable ferments are 
readily destroyed by boiling, and are for the most part 
very sensitive to acids and alkalies, a slight excess 
destroying them or stopping all action. They are not 
readily identified in tissues by use of stains. Some are 
very unstable. Enzymes have very slight power of diffu- 
sion. They can make their way through cell walls, but 
not through the parchment walls of dializers. They 
appear to act in an ordinary chemical way, causing hydra- 
tion (myrosin excepted) and subsequent decomposition. _ 
Most of the changes brought about by enzymes can be 
effected in the laboratory by ordinary chemical processes. 
They are extracted for experimental purposes by water, 
salt water, or glycerine, and are quickly precipitated by 
excess of alcohol. One of their most striking peculiarities 
is the enormous power of conversion they possess, a 
sample of invertase being capable of inverting 100,000 
times its own weight of cane sugar without injury to itself. 
The ferments of the fungi and bacteria are also enzymes, 
and the old view of Naegeli that there are two distinct 
classes of ferments, organized and unorganized, is no 
longer tenable. Enzymes have been isolated from a 
number of bacteria, and even several from the same 
organism,—in case of the potato bacillus, B. mesentericus 
vulgatus, no less than five, viz., diastase, invertase, 
rennet, a proteohydrolytic enzyme and one destroying the 
middle lamella of vegetable cells. 
MAPLES. 
In an interesting paper on ‘‘Sugar Maples, and Maples 
in Winter’ (Repr. from Fifth Annual Report, Mo. Bot. 
Garden), Dr. Trelease discusses the synonomy of certain 
species which has shifted about a good deal of late. He 
recognizes the western sugar maple as Acer grandiden- 
tatum Nuttall; the eastern, as A. saccharum Marshall 
with two varieties, barbatum (Michx.) Trelease, and 
nigrum (Michx. f.) Britton; the southern, as A. Florid- 
anum (Chapman) Pax, with variety acuminatum Trelease. 
The second part of the paper describes the winter 
appearance of all our species, the difference in bark, leaf- 
scars and buds being ample for their determination. The 
paper is accompanied by sixteen plates illustrating twigs, 
leaves and fruits. It was written partly for teachers, and 
it is to be hoped that it may find its way into the hands 
of a good many. Certainly there are hundreds who have 
no idea how interesting a study can be made out of bare 
twigs, and to whom this paper would prove very service- 
able. 
THE FOSSIL FLORA OF S. E. FRANCE. 
In May, 1893, at the Montpellier meeting of the 
Botanical Society of France, M. Saporta read a paper of 
twenty pages (recently published in Bull. de la Soc. Bot. 
d’France) showing the relationships of the living flora of 
Provence to that found in the rocks, especially of the 
Aquitanian. In the author’s own words, his conclusions 
are not drawn from simple and vague analogy, nor even 
from a more or less close morphological similarity, but 
rather from resemblances so close (¢zfime) as to be 
indications of a genuine filiation. In other words he 
supposes the living forms in question to be the direct 
‘throwing any light on problems of descent. 
SCIENCE. 117 
descendants from those whose fragments have been found 
in a fossil state. Only woody plants are considered, since 
herbs have left but insignificant vestiges too scanty for 
As pre- 
liminary to this consideration it should be borne in mind, 
first, that the farther back we go the fewer and the more 
vague and general are the resemblances of fossil plants to 
living ones, and, second, that the earliest relationships 
close enough to be considered filiative are with exotic 
species, growing generally in more or less restricted areas. 
Descendants of other early forms still occur in France 
but often in exceptional conditions of isolation and 
retreat. In more recent times, 7.c., toward the mio- 
pliocene, the flora changed gradually, the palms, laurels, 
magnolias, etc., which had long dominated, giving place 
to new elements probably derived from the north. These 
new-comers were principally oaks, of the Robur group, 
poplars, maples, and lindens. ‘Then only did the vegeta- 
tion of central and southern Europe begin to resemble its 
present condition. ‘The most ancient flora considered by 
M. Saporta is from the gypsum beds of Aix, which belong 
to the uppermost horizon of the Eocene. They have 
been explored for twenty years, and about 500 species 
are known. Fourteen species now indigenous to southern 
France so closely resemble forms from these beds as to 
be considered. their lineal descendants. These are: 
Ostrya carpinifolia, Quercus Ilex, Quercus coccifera, Olea 
Europea, Fraxinus oxyphylla, Nerium Oleander, Styrax 
officinale, Hedera Helix, Cornus mas, Paliurus aculeatus, 
Pistacia Terebinthus, P. Lentiscus, Rhus Coriaria, and 
Cercis Siliquastrum. Other types occurring in these 
beds are now represented only by exotic species, ¢.g¢., 
Callitris quadrivalvis in Algeria, Zizyphus spina-Christi 
in Tunis, Myrsine retusa in the Canaries, Amygdalus 
communis in Asia minor, and species of Ailanthus and 
Catalpa in eastern and southern Asia. In the oligocene 
many additional relationships appear. Notable among 
these new-comers are the ancestral forms of the California 
Sequoia, the N. Am. Taxodium, and the Chinese Glypto- 
strobus. These first appear in England and subsequently 
in southern France. The greatest interest, however, 
centres in the Aquitanian flora. From the Manosque 
beds of this horizon there are no less than thirty ancestral 
forms of exotic species. These species, although long 
excluded from France, have varied so little that they 
cannot be separated from their presumed ancestors. 
Among them are Sequoia sempervirens in California, 
Sabal umbraculifera in America, Myrica salicina in 
Abyssinia, M. sapida in Nepaul, M. Faya in the 
Canaries, Betula cylindrostachya of interior Asia, Alnus 
subcordata of the Caucasus, Carpinus viminea of Nepaul, 
Fagus ferruginea of America, Populus Euphratica of 
Algeria, Syria and Palestine, Zelkovia crenata of the 
Caucasus, Z. Protokeoki of Japan, Persea gratissima of 
the Tropics, Nelumbium speciosum of southern Asia, 
Magnolia grandiflora of Louisiana, Acer crateegifolium of 
Japan, Acer rubrum of America, A. rufinerve of Japan and 
A. sp. of interior China, Berchemia volubilis of America 
and an unnamed similar species from Yunnan. Among 
the species which, with slight modifications, have held 
their own in southern France from the Aquitanian down 
are the following: Juniperus Oxycedrus, Smilax mauri- 
tanica, Alnus incana, Carpinus orientalis, Ostrya carpini- 
folia, Fagus silvatica (through one or several intermediate 
forms in the mio-Pliocene), Salix fragilis, Populus nigra, 
P. alba, P. Tremula, especially Asiatic varieties of the 
type Tremula, the southern variety of Ulmus montana, 
Laurus nobilis, Fraxinus oxyphylla, Olea Europea, Styrax 
officinale, Acer opulifolium, A. Opulus, A. campestre, 
Rhamnus frangula, and Cydonia vulgaris. The Aqui- 
tanian is still a long way from modern times. In the pre- 
