228 
POPULAR SCIENCE REVIEW. 
horizontally, with a lever and index at the end, where there is a rotating 
cylinder to receive impressions, and a clock to produce them by pressing the 
index at stated intervals. The magnets are on Lainont’s model. 
The 85th Asteroid has been named Io, a designation open to the objection 
that it already belongs to one of the satellites of Jupiter. 
Secchi, in the Bulletino Meteorologico, asserts that the bluish-green light 
which fringes the red moon in a lunar eclipse is merely an effect of contrast. 
The assertion is founded on observations made with a very small field of 
view. 
ERRATA. 
We regret that the printer took considerable liberties with our last Astro- 
nomical Summary. The reader is requested to make the following altera- 
tions : — 
Page 91, 
line 3 of text, 
for Lcewig 
read 
Loewy. 
55 
94, 
„ 11 from top, 
„ vibration 
libration. 
55 
94, 
„ 18 from top, 
„ Dane’s 
55 
Dawes’. 
55 
94, 
„ 3 from bottom 
, „ Poulhower 
Poulkowa. 
55 
95, 
„ 18 from top, 
„ on 
55 
in. 
55 
95, 
„ 20 from top, 
after elongate 
insert 
Y Andromedse. 
BOTANY. 
The Influence of Light on the Twining Organs of Plants. — At a meeting of 
the French Academy, held on Oct. 26th, a valuable paper on this subject was 
read by M. Duchartre. The memoir deals with the questions already dis- 
cussed by Mr. Darwin, and alluded to in an article in our last number. The 
French botanist records his own experiments and those of other observers, 
and concludes that there are two groups of twining plants : 1. Such plants 
as Dioscorea Batatas and Mandevillea suaveolens, which have the power of 
attaching themselves to surrounding objects only under the influence of light. 
2. Species, such as Ipomosa purpurea and Phaseolus , which exhibit this power 
equally well in light and darkness. 
The proper Vessels of the Aroidece. — M. Trecul continues his inquiries in 
this department of structural botany with much perseverance and considerable 
success. He describes especially the true vessels. These are canals with an 
oleo-resinous juice, and formed by two or three rows of small oblong cells, 
which are narrower than those of the surrounding parenchyma. They exist 
in the leaves, stems, and adventitious roots. In the blade of the leaf they 
are arranged parallel to the veins. The resinous matter which they contain 
is generally colourless in the roots ; but in the stem and leaves it assumes a 
yellowish colour, passing to orange and red. In some Aroidese there are, he 
says, two modifications of the vascular bundles, which he terms respectively 
simple and compound. The simple bundles have the character of the vascular 
bundles of the Monocotyledons ; they are formed of a vascular part, properly 
