383 
agitating: a dilute alcoholic solution with chloroform. If so 
much alcohol be added as only to partially dissolve the chlo- 
roform, scarcely a trace of the magenta is left in the alcoholic 
solution, and the characteristic spectrum can be easily seen by 
examining the chloroform, which scarcely abstracts any other 
colour. Ammonia produces no change in a solution of 
magenta in dilute alcohol, hut the absorption band is imme- 
diately removed by a mere trace of sulphite of soda. 
It would scarcely be a correct description of the facts to 
say that cochineal may easily be detected in pink-coloured 
confectionery, since in some cases its spectrum is seen to 
almost as great advantage as in any condition without any 
preparation ; and it could generally be recognised with very 
little manipulation. 
No doubt many other applications of methods similar to 
those I have described would present themselves to any one 
engaged in technical inquiries. I do not for one moment 
pretend to have exhausted the subject. I have merely ex- 
amined various questions in older to ascertain what methods 
might be employed with advantage, and I trust that the cases 
described above will, at all events, facilitate the application 
of this kind of qualitative analysis to practical questions, 
for I have met with many who w r ere anxious to employ it, 
but had not sufficient time at command to make the prelimi- 
nary experiments, which are so very necessary in all such 
inquiries. 
On Draparnaldia cruciata, Hicks. 
By J. Braxton Hicks, M.D., F.R.S. 
With Plate XIX. 
The Draparnaldia, of which a drawing for the first time 
is now given, was described by me in the ‘Journal of the 
Linnaean Society, 5 November 18th, 1857. It was discovered 
by me in the gentle streams issuing from the bogs of the 
New Forest in several localities. Subsequently, among 
some drawings sent to me by Mr. G. S. Brady, Secretary 
of the Tyneside Naturalist Field Club, in order to be named, 
I was pleased to find a very accurate representation of this 
alga. It was found by him in the peat bogs near Crag 
Lough, Northumberland, and is mentioned by him, along 
with others found in the same locality, in the sixth volume of 
the ‘ Trans. Tyneside Naturalist Field Club.’ 
The species is remarkably distinct from the others hitherto 
