a 
Feb. 15, 1883 | 
NATURE 
379 
sary physical knowledge, they may expect efficient aid towards 
introducing order and causality: among their valuable observa- 
tions. 
Mathematical Society, February 8.—Prof. Henrici, F.R.S., 
president, in the chair.—Capt. P. A. MacMahon, R.A., was 
admitted into the Society—The following communications 
were made :—On the Sylvester-Kempe quadruplane, by Mr. H. 
Hart.—On curves obtained by an extension of Maclaurin’s 
methed of constructing conics, by Mr. S. Roberts, F.R.S.—A 
generalisation of the ‘‘nine-point”’ properties ofa triangle, by 
Capt. P. A. MacMahon.—On the use of certain differential 
‘operators in the theory of equations, by Mr. J. Hammond.—A 
method for reducing the differential expression d¢/./{¢—a, ¢- B, 
¢—y, 7-5} to the standard form, by Mr. J. Griffiths. The 
‘‘nine-point’”” property was the following :—If through the 
centre of the circle 4 #C, and the ortho-centre of the triangle 
ABC, lines be drawn making angles a and r—a with the sides 
of the triangle, twelve points will be obtained on the sides, and 
these lie six and six on two circles of radius } R coseca. Each 
circle also passes through six other points, and they are inscribed 
circles of the two three-cusped hypocycloids, which are the 
envelopes of the two tangents, equally inclined to the axis (at 
angles a), to a parabola inscribed in the triangle ABC. Of 
course, when a = 4, the circles become the ordinary nine-point 
2 
circle of ABC. 
Linnean Society, February 1.—Sir John Lubbock, Bart., 
F.R.S., president, in the chair.—Messrs. F, W. Burbidge and 
Joseph Johnson were elected Fellows of the Society.—Dr. W. (Gs 
- Ondaatje called attention to examples of red coral from Ceylon. 
| —Mr. W. T. Thiselton Dyer exhibited a model of the fruit of 
the Double Cocoa-nut (Lodoicea Seychellarum, Lab.), of an 
unusual form, obtained from Major-General C. G. Gordon, R.E. 
—A series of microscopic sections of coal-plants were shown on 
behalf of Mr. J. Norman.—The fullowing paper was then 
read :— On the structure, development, and life-history of a 
tropical epiphyllous lichen, by H. Marshall Ward. The author’s 
observations lead him to believe that the epiphyllous cryptogam 
in question supports the view that a lichen is a compound organ- 
ism composed of an alga on which an ascomycetous fungus has 
become more or less intimately affixed and dependent. It is 
developed on the leaves of many plants, but it has been more 
closely watched on AZichelia furcata. The lichen presents four 
types, orange-red stellate patches, greyish-green blotches, clear 
grey spots, and white shining circles, but these pass impercept- 
ibly into one another, and vary in size from a speck to a quarter 
of an inch in diameter. The reddish spots of the earlier stages 
is an alga of which the radiating filaments are in part reproduc- 
tive organs, and in part barren hairs. It subsequently passes 
into the grey and green stages, and by a modification of growth 
the invasion of a fungus mycelium succeeds. The white matrix 
of the complete lichen consists of the same algal thallus invested 
by dense masses of the fungus hyphze, which produce shining black 
dots, viz. the fruit bodies. The author describes in detail the pecu- 
liarities of growth and reproduction of the alga and fungus, and for- 
mation of the lichen. He alludes to and criticises Dr. Cunningham’s 
account of Mycotdea parasitica, which latter is evidently closely 
related to that described by himself, Assuming that Mycoidea and 
Ward’s Alga are generically the same, either Cunningham 
discovered a female organ of reproduction which becomes 
fertilised and produces zoospores, or he confounded these 
with certain fertile hair organs described by Ward. As re- 
gards the systematic position of the alga, a comparison with 
Coleocheta suggests that there is very little in common le- 
yond mode of growth of the disc-like thallus, and the pro- 
duction of zoospores from certain cells. The genus Chryoolepus, 
moreoyer, presents features which agree in several important 
points, viz., orange-red oily-cell contents, habitat, production of 
zoospores in ovoid cells developed terminally and laterally, The 
structure of the thallus, and relative positions of the main masses 
of fungal and algal portions, agree with what occurs in hetero- 
merous crustaceous lichens, as Graphidea ; but the perithecia 
indicate an angiocarpous alliance, bringing this form nearer such 
families as Pertusaria and Verrucaria, to the latter of which it 
may ultimately be referred.—A paper was read by F. Maule 
Campbell, on the pairing of 7zgenaria Guyoniz, and description 
of certain organs in the male abdominal sexual region. Two 
cases are related in which during confinement the males killed 
the females after union, and an instance is also given of an 
attempt to impregnate an immature female which was also 
destroyed by the male. In neither case could hunger have been 
the cause of the attack. The writer explains the occurrences, 
and also the accounts of females destroying males after union, 
on the ground “that those instincts which are habitually prac- 
tised throughout the far greater portion of the life of the species, 
and on which it is dependent, would scarcely be suspended for a 
longer period than necessary for the sexual union.” Some of the 
habits of spiders, and especially of this species, are mentioned 
as bearing on these sexual conflicts, and the specific benefits 
which would arise from them are referred to. The paper con- 
cluded by a note on some glands (probably for spinning) situated 
on the convexity of the abdominal sexual region. The ducts 
are con-iderably convoluted, and open through transparent tubular 
spines which are arranged transversely to the axis of the body of 
the spider. Two papilla-like processes below the opening of the 
genital sinus are described. 
Zoological Society, February 6.—Prof. W. H. Flower, 
LL.D., F.R.S., president, in the chair.—A letter was read from 
Mr. F. C. Selous, dated from the Matabele Country, on the 
possibility of obtaining a White Rhinoceros.—Extracts were read 
from a letter received from the Rev. G. H. R. Fisk, C.M.Z.S., 
of Cape Town, giving an account of the habits of some reptiles 
which he had had in captivity.—A communication was read 
from Messrs. Salvin and Godman, containing the description of 
a new species of Pigeon of the genus Ofdiphaps from Ferguson 
Island, one of the D’Entrecasteaux group, which they proposed 
to call O. insudaris—Mr. Sclater read some further notes on 
Tragelaphus gratus, and exhibited drawings of both sexes of 
this antelope, taken from specimens living in the Menagerie of 
the Jardin des Plantes, Paris. —A communication was read from 
Mr. E. W. White, F.Z.S., containing some supplementary notes 
to a fofmer paper on the birds of the Argentine Republic.—A 
communication was read from the Rev, G. A. Shaw, contain- 
ing some notes on the habits of an Aye-Aye which he had had 
in confinement for several months, and other information respect- 
ing this animal.—Mr G. A. Boulenger, F.Z.S., read a paper 
containing the description of a new species of Lizard of the 
genus Zmyalius from Peru, which he proposed to name &. 
palpebralis. 
BERLIN 
Physiological Society, January 12.—Prof. du Bois Reymond, 
in the chair.—Dr, Falk read a contribution upon the phenome- 
non lately demonstrated by experiments on animals, that great 
oedema of the lungs can be produced in a very short time. even 
in a quarter of an hour, by compressing or otherwise interrupting 
the function of the left side of the heart; w ereas a similar 
action on the right side does not produce such ‘n effect. Dr. 
Falk has had an opportunity in two post-mortems of proving 
the correctness of these observations in respect to man, In one 
of these cases, a strong, healthy man died in consequence of a 
discharge of shot, and the post-mortem showed that the cause of 
death was the penetration of a shot into the wall of the left 
ventricle, The lung of this previously healthy man exhibited a 
high degree of oedema. In the second case, a healthy railway- 
workman was killed by a blow of a buffer upon the chest. Tne 
post-mortem showed a rupture of the right ventricle to have 
been the cause of death; the lungs which were carefully 
examined, did nct show a trace of oedema,—Dr. W. Wolff 
described the structure of the tactile c>rpuscles, according to his 
researches, they contain no nerve-branchings, but consist of a 
rugose sheath, granular contents, and the free ends of the enter- 
ing nerve-fibres. In opposition to other histologi-ts he further 
found the epithelium-cells which he studied in the cornez of 
small mammals to be devoid of nerves ; and in agreement with 
this he has always found gland-cells to be withour nerve, Tne 
sympathic nerve-fibres which enter into the glands according 
to Dr. Wolff always end in unstriped muscles. —Prof. Kronecker 
reported on experiments of Dr. Meiss, upon the irritability of 
the heart under abnormal conditions of nutrition. During experi- 
ments, undertaken to study the comparative effects of concen- 
trated and diluted blood upon the frog’s heart, and which 
established the occurrence of a more energetic activity by 
nutrition with conceutrated blood, certain remarkable deviations 
oceasionally occurred from the general law that frog’s hearts 
(always) respond to every stimulation with maximal contractions. 
These deviations consisted in the occurrence of smaller sub- 
maximal beats between the maximal beats. [Further investiga- 
tion of this appearance led to the conclusion that this was a 
