88 C. A. MAC MUNN. 
some shading at the blue end of green. When placed in 
absolute alcohol the latter was found to have become yellow, and 
then showed a feeble shading at the blue end of green with its 
darkest part from about 4503 to A468, but the amount of 
colouring matter obtained, as may be supposed, was very small. 
The pale red residue from an alcohol solution was soluble in 
chloroform with a reddish-yellow colour, and in ether with a 
yellow colour. The residue became blue and greenish with 
nitric acid, greenish and bluish green with sulphuric acid, 
and reddish with iodine in iodide of potassium. Hence it was 
a lipochrome resembling rhodophan or xanthophan. 
CRUSTACEANS. 
I have not had an opportunity of examining many crus- 
tacean pigments besides those which I have described in 
former papers. In Astacus fluviatilis I find that the 
hypoderm is coloured by a red lipochrome! resembling rhodo- 
phan. Its solutions absorb the whole spectrum except red 
and a little green in a deep layer, while in a shallow layer one 
very broad band occurs in the middle of the spectrum. This 
pigment is soluble in chloroform with a fiery red, in ether with 
an orange red, in bisulphide of carbon with a red, and in 
petroleum ether with an orange-yellow colour. The red 
residue from any of these solutions was coloured a fine blue 
and greenish with iodine in iodide of potassium, greenish blue 
and blue with sulphuric acid, and a fine but transient blue 
with nitric acid. 
In Homarus vulgaris I found that the colouring matter 
of the hypoderm dissolved in absolute alcohol, ether, chloroform, 
bisulphide of carbon, &c.; in addition to absorbing all of the 
spectrum except red and a little green in a deep layer the 
alcohol solution gave a band in red; coincident with the 
same band in an alcohol solution of the so-called 
liver. This would go to prove that the enterochlorophyll of the 
liver may be carried to the hypoderm and changed there into a 
1 T called this tetronerythrin formerly, and would be correct in doing so now, 
as it corresponds exactly to the description of that pigment. 
