SCIENTIFIC SUMMARY. 
195 
lished another valuable paper on the laws of solar spot-frequency. The chief 
points in this paper are the following : — First, the average period from mini- 
mum to maximum spot-frequency is 34 years ; the average from maximum 
to minimum 6-9 years. Secondly, a retarded ascent to the maximum is 
followed by a retarded descent to the minimum, an accelerated ascent by 
an accelerated descent. Professor Wolf had enunciated the theory that a 
retarded or accelerated descent to the minimum is followed by a retarded or 
accelerated ascent to the maximum. Messrs. De La Rue, Stewart, and 
Loewy, after carefully comparing the evidence for the two theories, consider 
that their own is fully made out. It should be added that, on a priori 
grounds, their theory appears far the more probable. 
Flanets for the next Quarter— Jupiter will be in quadrature on April 10, 
and is passing too far to the west to be altogether well placed for observa- 
tion, though he will form a’fine object in our evening skies for the next few 
months. Uranus will be in quadrature on April 16, and in conjunction with 
Jupiter (very close) on June 5, at 6h. 11m. p.m. Saturn will not be well 
placed for observation till towards the end of the quarter, when he will be 
approaching conjunction, which he reaches on July 9. Mars and Venus will 
not be well placed for observation. 
Partial Eclipse of the Moon . — There will be a partial lunar eclipse, visible 
at Greenwich, on May 22. The following are the mean times of the chief 
phases at Greenwich : — 
H. 
H. 
First contact with the penumbra 
9 
9-8 
„ „ shadow 
. 11 
40-9 
Middle of the Eclipse . 
. 11 
18-2 
Last contact with shadow . 
. 11 
55-5 
„ „ penumbra 
. 13 
26-6 
The first contact with the shadow will occur at 177° from the north point 
of the moon’s limb towards the east ; the last contact at 143° towards the 
west (in each case, for direct image). The magnitude of the eclipse (moon’a 
diameter =1) will be 0416. 
BOTANY. 
A somewhat rare Fungus, the Xenodochus Carbonarius, has recently been 
presented to the Manchester Philosophical Society by the Rev. J. E. Vize, 
M.A., who stated that it occurs near Welshpool, in a railway cutting, with 
a south-westerly aspect, well sheltered by a hill and a wood. The first 
appearance on the leaves of Sanguisorba officinalis, L., was noticed in the 
middle of May, when the Lecythea-form was in perfection, but the stems 
and other portions of the Burnet were greatly distorted by it. A month 
afterwards the magnificent vermilion-coloured spores were well sprinkled* 
over the leaves, the form of which was unaltered. In the middle of July, 
the intensely black brand-spores made their appearance, many of which had 
twenty or more articulations, and were plentifully scattered over the leaves 
in tufts. Mr. Vize stated that he had not watched the transition state from 
the Uredo to brand-spores, but he hoped to do so if opportunity offered. 
