SCIENTIFIC SUMMARY. 
79 
ward to tlie approach of so rare and so instructive a phenomenon ; and those 
who have the means of influencing the success of the observations or expe- 
ditions undertaken by men of science, will spare no endeavour to secure a 
favourable result. Cloudy weather at a few critical stations may of course 
render all their exertions useless. It is, in fact, impossible for astronomers, 
as for other mortals, to 11 command success; ’ but, judging from the past 
history of the science, we may feel sure that they will “ deserve it.” 
BOTANY. 
The Formation of Oil in Olives. — At the meeting of the Vienna Academy 
of Sciences on October 21, a memoir by Herr Harz was presented to 
the class on the above subject. The author thus classified his results in 
summarising his paper : — 1. This secretion in its first formed condition does 
not possess the common properties of the fat-oils. 2. It is inclosed almost 
till its complete development in true secretion-cells, the walls of which 
can be made visible by re- agents. 3. These secretion-cells are not simple, 
but contain within themselves a number of other secretion-cells (daughter- 
cells), which, gradually developing, are finally converted into oil, while the 
membrane of the mother-cells itself also changes into oil. 4. This mem- 
brane was rendered visible by treatment with Miller’s salt, or still better, 
first with this salt, then with aniline solution, and lastly with iodised 
chloride of zinc, these three reagents together colouring it a beautiful deep 
blue. 
The Classification and Nomenclature of the Species and Varieties of Toy . — 
Mr. Shirley Hibberd, who is well known to our readers as a successful hor- 
ticulturist, admits three species of Hedera. He proposed the following 
subdivisions : — 1. Scandent, or climbing ivies, with green leaves ; 2. 
Scandent, or climbing ivies, with variegated leaves ; 3. Arborescent, or 
fruiting ivies, with green leaves ; and 4. Arborescent, or fruiting ivies, with 
variegated leaves. u Under one or more of these four subdivisions may be 
placed every garden ivy known.” u A very brief experience with ivies will 
convince the observer that every scandent form tends inevitably to the 
fruiting form, requiring only age and immunity from the pruning-knife to 
produce in due time abundance of berries. It is not, however, so generally 
known that every fruiting form, however arborescent, is capable of revert- 
ing to its corresponding scandent form ; the mere opportunity for climbing — 
as, for example, proximity to an old brick wall — and the roots having free 
range in a rich soil, tending to what may be properly termed its rejuven- 
escence.” — Paper before Linncean Society , November 18. 
Chlorophyll and its Optical Properties was the subj ect of a communication 
to the Ashmolean Society of Oxford at a meeting on Nov. 29. It was, 
however, little more than a summary of Smith’s, Stokes’, and Bay Lankester’s 
inquiries. 
Spasmodic Movements in Leaves. — We learn from a contemporary that 
M. Lecocq records ( Belgique Horticole ) some curious movements which he 
has observed in the leaves of Colocasia esculmta. The motion is of a peculiar 
quivering kind, very unlike that of Mimosa , and is somewhat forcible. 
