II4 
‘NATURE 
as regards the shape of their tendons. Just along outside the 
muscles are dark lines more or less well finished, and resulting 
from the action of the muscles. - Ubi trritatio ibi affiuxus, I 
believe that it would not be unphilosophical to conclude that a 
powerful action in the development of the muscles is, in such a 
case, the cause of a greater combustion or oxidation in the 
neighbouring parts. In fact, on the head of a Cicada and on the 
abdomen of an /Eschna we find similar patterns, in some way 
mostly representing the underlying muscles. In the Gomphina 
the fact is striking, and far more as the stronger species mostly 
possess a large dark pattern. There are some very small species 
which are almost entirely yellow; there are no small species 
entirely black. 
Should the fact, with the explanation, be admitted, a step 
farther in the explanation of the different patterns would be 
made. I know very well that in the Odonata there are patterns 
which do not agree with my explanations, even some contrary 
to it; but if some certain facts be explained, there are perhaps 
more factors still unknown or unobserved. The explanation for 
certain facts would still be admissible, or at least not entirely 
objectionable. * 
The patterns on the wings and elytra could not be the product 
of the action of muscles, but I believe it to be probable that the 
sudden rush of blood, or even air, by the accelerated circulation 
and respiration in the act of transformation may have the same 
effect. In this way some patterns, otherwise not explicable, 
could be understood. The eyespots in the caterpillars of some 
Papilionidze have been ascertained by Leydig to be epidermal 
colours, and I believe that the various kinds of eyespots in the 
wings of the imago are also epidermal colours. If a stream of: 
blood meets a small obstacle just in the centre, a funnel is 
formed ; if this obstacle is a ring, and behind it.another obstacle, 
we have two or more funnels, one in the other, and the section 
of them will be circular or elliptical according to the angle at 
which they reach the surfaces. Such patterns in the elytra and 
wings are formed or preformed at the time when the wing is a 
sac; sometimes before the transformation, and here is another 
circumstance which explains some patterns. The walls of the 
sac are suddenly augmented and strongly dilated in the trans- 
formation. Small patterns performed in the sac will also be 
altered and enlarged by the same process, and I know that many 
patterns of Lepidopterous wings are in such a way very easily 
explained. All the waved lines of the wings and other marks 
belong here, and as the ribs or nervures seem to grow faster in 
transformation, the waved appearance would be explained In 
fact the greater part of the patterns seem to be produced by ex- 
pansions or distraction of the pattern performed in the wing at 
some period before the transformation. H. HAGEN 
SCIENTIFIC SERIALS 
THE Monthly Microscopical Fournal for October 1872, con- 
tains a continuation of Dr. Robert Braithwaite’s papers on bog 
mosses, the present communication being confined to Sphagnum 
neglectum Angstr. Dr. J. J. Woodward contributes a reply to 
further remarks on Tolles’ 4th and Powell and Lealand’s ;'yth. 
This is succeeded by a communication ‘‘ On the History, Histo- 
logical Structure, and Affinities of Vematophycus Logani Curr. 
(Prototaxites Logani Dawson), an Alga of Devonian Age,” by 
Wm. Carruthers, F.R.S., in which the author combats the 
* So faras I kn ow the literature relating to the phenomena of mimicry, 
all these related differences are often confused, and I believe that in sepa- 
rating them and following the views above given, many facts would be better 
understood, and this interesting subject more easily advanced. 
sides all the difficulties which oppose a clear and correct view, there is 
one more which I do not find mentioned, z.e. the so-called colour-blindness, 
and the different degrees of it. Prof. B. A. Gould in his excellent work, 
“Investigations on Anthropological Statistics of American Soldiers,”’ has 
given attention to it in a very remarkable chapter. Persons who cannot 
distinguish ripe cherries upon the tree, or strawberries on the vine by their 
colour, are far more numerous than would be suspected. Serious misunder- 
standings, and even calamities, have been reported in the army, resulting from 
mistakes in the colour of green and red light by officers of the signal corps, 
He gives the statement that usually one in twenty, and in the soldiers 
examined one in fifty, was subjected to colour-blindness.. But these numbers 
show only the extremes; and it is easy to believe that a much greater 
number are more or Jess affected with it. In fact, we have no means of 
measuring this physiological difference ; if two persons call something green, 
and even compare the colour with certain known objects, there is no proof 
at all that they see just thesame colour. Ithink that it would be prudent in 
describing cases of mimicry, especially when they are extraordinary, not to 
forget that even the best observer may be unaware of this infirmity, anc in 
fact the best authorities on colour -blindness always state that the greater 
number of persons haye no idea of their infirmity. 
‘Aromatic Azodiamines.” 
theory advanced by Dr. Dawson, that the fossil in question i 
coniferous, and contends that it is cryptogamous, belonging to a. 
gigantic alga, of the class C/lorospermee. , Two plates a 
pany this very interesting and important communication. — 
the active part of the Nerve Fibre, and on the probable natu 
of the Nerve Current,” by Lionel S. Beale, F.R.S., is a fw 
contribution to the researches for which Dr. Lionel Beale 
earned a reputation.—‘t On the Régeneration Hypothesis,” by 
Dr. Louis Elsberg, of New York. The fundamental proposi 
of this hypothesis is thus stated by its author; ‘* The germ 
every derivative living being contains plastitudes of, its whi 
ancestry.” —Dr. J. J. Woodward contributes some observati 
on the use of monochromatic sunlight, as an aid to high-po' 
definition.—A short paper by Prof. Albert H. Tuttle, on 
our common monads is from a communication made to 
microscopical section of the Boston Society of Natural History. 
Bulletin de l’ Académie Royale de Belgique, No. 8. 
number contains a mathematical paper of some length, 
M. P. Mansion, on singular solutions of differential equat 
the first order; also a note by M. Dubois describing. 
researches on the camphors. He studied the action of pe 
phuret of phosphorus at a high temperature on monobro 
camphor, and found that it gave cymol, accompanied with s 
quantities of hydrocarbons of the same homologous series, 
an organic sulphhydrate soluble in alkalies. M. Alphoi 
Waters gives a sketch of some efforts that were made in Bel; 
in the middle of the 17th century towards the establishment 
free trade.—A note by M. Schuermanns treats of the disco 
of objects of amber in Belgium, the writer advising a sp 
study of the circumstances which may have connected Bel 
with the commercial route from Etruria to the country of amb 
on the Baltic. 
SOCIETIES AND ACADEMIES 
LoNDON 
Royal Society, Dec. 5.—‘‘ Colouring-matters derived 
II, Safranine. By Drs. A. 
Hofmann, . F,R.S., and A. Geyger. ; 
Whilst we were engaged with the study of the blue colou 
matters produced by the action of aromatic monamines 
diphenyldiamine, our attention became directed to a bea' 
red tar-pigment, which has been known for some time by 
commercial name of Safranine, being extensively used a 
substitute for safflower in dyeing silk and cotton. Safran 
has not as yet been minutely examined ; but, as far as 
judged from the scanty information we possess regarding 
production, it is scarcely doubtful whether this important dye 
be looked upon as being the derivative of an azodiamine. 
analyses of safranine thus promised to throw considerable light 
upon the nature of the compounds under examination. ae ‘ 
y 
Saframine occurs in commerce either as a solid b 
en pate. n the solid state it forms a yellowish-red powd 
which, together with considerable quantities of chalk 
common salt, the chlorhydrate of a tinctorial base has 
recognised. The pure dye may be easily separated ‘rom 
crude safranine. It is only necessary to exhaust the comm: 
product with boiling water ; on cooling, the filtrate deposits 
slightly crystalline substance, which, after several recrystall 
tions from boiling water, leaves no residue onignition. Du 
thes2 operations, however, the salt undergoes perceptible al 
tion; with. every recrystallisation it becomes more soluble 
less crystalline, These alterations depend upon the sepa 
of chlorhydric acid from the salt. In fact the percentage 
chlorine is found to diminish in the product of succesive erystal- 
lisations ; thus the product of the third contained 8-48 4 cent, 
that of the fourth crystallisation only 7°46 per cent. Addi 
of chlorhydric acid to the mother-liquors at once reprodu 
crystalline precipitate. This instability of the chlorhydrate, a 
in’ fact, as may even now be stated, of the salts of safranine 
general, bas very considerably impeded the study of this 
and often materially affected the accuracy of the analyti 
results, In_order to obtain the normal salt, the boiling liq 
during the last crystallisation had always to be acidified with 
chlorhydric acid. y a 
‘« Synthesis of Aromatic Monamines by Intramolecular Atomic 
Interchange.” By Dr. A. W. Hofmann, F.R.S. a 
In 2 paper submitted to the German. Chemical, Society about 
a year ago, we proved (Dr. Martius and myself) that the action 
sdeke 
