60 C. A. MAC MUNN. 
“Actinometra stilligera.” A yellowish solution which 
on evaporation in vacuo left a yellowish-brown residue, sol- 
uble in rectified spirit with a yellow colour; this absorbed 
the violet but showed no bands. Hydrochloric acid left the 
colour of the solution unchanged; with caustic potash it 
became a brownish yellow, but showed no bands. The 
residue failed to give the lipochrome reactions. 
Evidently the Antedons contained a pigment related to 
that of A. rosacea, while of the Actinometrz two con- 
tained altered antedonin. The amount of colouring 
matter at my disposal in each case was very small, which 
accounts for the unsatisfactory descriptions. Still in those 
cases where antedonin had been present traces of it could still 
be recognised. 
Holothuria nigra.—The dark brown and the yellow 
pigment of the integument of Holothuria nigra, gave no 
absorption bands. In the blood-vessels I failed to find any 
hemoglobin ; on the contrary, the blood strongly absorbed the 
violet end of the spectrum but gave no bands. The blood- 
colouring matter is soluble in absolute alcohol, forming a deep 
yellow solution, giving an ill-defined band at the blue end of 
the green, beginning to be feebly shaded at about A 526, darker 
at X 507, and extending to about A474. On evaporation it 
left a reddish residue soluble in ether, in chloroform, and 
other lipochrome solvents, and when in the solid state it 
became a transient blue with nitric acid, blue, green, and 
brownish with sulphuric acid, and greenish yellow with iodine 
in potassic-iodide. ‘Therefore, the blood of Holothuria 
nigra contains a red lipochrome like that of certain Crus- 
taceans, as Dr. Halliburton has discovered.! Taken in con- 
nexion with the results of the examination of the organs of 
this animal, this observation is very interesting. 
The Polian vesicle contained a purplish pigment which 
gave an ill-defined band at p, and squeezed out thinly, a shading 
at the blue end of green; when placed in absolute alcohol it 
tinged the alcohol a deep yellow colour, and this solution in a 
1 “ Blood of Decapod Crustacea,” ‘Journ. Physiol.,’ vol. vi, No. 6. 
