WEDNESDAY, MAY llth, 1892. 
AN EVENING FOR CONVERSATION, THE 
EXHIBITION OF SPECIMENS, &c. 
Mr. Edward Crane, F.G.S. (Chairman of the Museum 
Committee) called particular attention to a species of two-toed 
sloth belonging to the Museum (Cholepus Hoffmanni). Its hair 
is in life covered with a species of green alga. This extraordinary 
growth, of which no remains exist in the stuffed specimen, must 
be of great advantage to an arboreal creature like the sloth, 
which seeks its food among the green leaves and branches of 
trees ; its colour affording it also protection from its enemies, 
sleeping as it does among the branches during the greater part 
of the day. The sloths are inoffensive, nocturnal animals. They 
possess great tenacity of life and survive severe injuries. 
Professor Kitchen Parker considered the evolution of protective 
characters as better seen in this group than in any other. The 
dry, shaggy character of the hair makes them inconspicuous 
among the trees of the forest, and it is enhanced by the greenish 
tint of this outer covering—which is not common in mammals. 
This is not due to the colour of the hair, but to the presence upon 
its rough surface of an alga, which grows upon the fluted surface 
of the hair. This strange growth is promoted by the dampness 
of the forests in the tropical regions which the creature frequents, 
for the genus occurs only in Brazil and Central America. The 
alga disappears when the animals are kept in captivity in this 
country. 
Miss Agnes Crane exhibited a specimen of the long-tailed 
trogon from South America (Trogon resplendens), and remarked 
that it was the sacred Quetzal of the ancient Aztecs and now the 
national emblem of the State of Guatemala. The specimen exhi- 
bited was a male. The two enormous tail feathers being developed 
on the male bird only, the female being small and sober-coloured, 
and devoid of these extraadornments. The Quetzal’s tail plumes 
were much valued by the ancient Mexicans, and large numbers of 
the birds were shot simply for the plumes, as they were used in 
the decoration of the Aztec idols or images of hero-gods, and 
their use was otherwise restricted to the chief priestly warriors 
or “‘ supreme war-lords ”of Mexico, who wore head-dresses formed 
