512 
PROFESSOR A. H. CHURCH ON TURACIN, 
their African homes, and from which they might have derived the copper necessary 
for the formation of their cupreous pigment. Such a suggestion appears, however, of 
doubtful value, for the plantain-eaters are arboreal feeders ; and it is unnecessary, 
since copper is now known to be very widely distributed in plants, and I have shown 
it to be present in decided traces in bananas, the chief food of many species of Touraco 
In 1881 Dr. M. Giunti published a paper entitled “ Ricerche sulla Diffusione del 
Kamo nel Regno Animate.”* This memoir gives a resume of the work previously 
done on this subject, but also contains many new observations. Dr. Giunti found in 
the ash of the animals and animal products named below the following percentages of 
copper oxide (CuO) :— 
Chrysomela americana .D293 
Lizard skins, Podarcis muralis .I - 049 
Blatta orientalis .0‘826 
Bat-guano (from Calabria).0 - 817 
Catonia hirtella .0'661 
Julus terrestris .. . 0’221 
Swallows.0'217 
Armadillidium vulgare .0‘197 
Helix pisana. . . . 0’089 
Hedgehog . . . 0'016 
These results are of value not only as confirming the view that copper is widely 
diffused in the animal kingdom, but because they render probable further discoveries 
as to the occurrence of definite organic cupreous compounds in nature. 
The researches of Dr. C. F. W. Krukenberg, on “Die Farbstoffe der Federn,”t 
must now be considered. This investigator has described a green colouring matter 
obtained from the green feathers of Turaeus corythaix, and of other plantain-eaters, 
by the employment of a 2 per cent, caustic soda-solution as the solvent. He calls this 
pigment “ turacoverdin,” and, although he did not obtain enough of it for quan¬ 
titative analysis, states that it contains “ much iron, but no great quantity of copper 
and manganese,” and that “ perhaps, like turacin, it is free from sulphur and 
nitrogen.” Here I must observe that Dr. Krukenberg, on referring to my paper on 
turacin, with which he was acquainted, would have found that turacin contains 
between 6 and 7 per cent, of nitrogen. The Author goes on to say : “ This colouring 
matter (turacoverdin) becomes of high interest through the results of the experiments 
made by Church on turacin.” And then he proceeds as follows—I quote the 
original German of Dr. Krukenberg —“ In seiner ausgezeichneten Arbeit uber das 
Turacin—einem, auf dem Continente durchaus unbekannt gebliebenen und von mir in 
der grossen Katakombe des ‘Philosophical Transactions’ deshalb aucli erst so spat 
aufgefundenen Meisterwerke auf dem Felde der physiologischen Chemie—mit welcher 
'* ‘ Accademia Reale delle Scienze,’ Napoli, 1881. 
t Heidelberg, ‘ Vergl.-physiol. Studien,’ 1881. 
