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very pretty but extremely common species tlie 0. cenea, 
in which the male is of a rich bronzy tint, and the female 
of a beautiful blue, verging sometimes to nearly black, 
burrows also in wood, although sometimes it capriciously 
selects old walls or chalk-cliffs, and is subject to the 
incursions of the same parasite. Perhaps the most 
extraordinary species is the 0. parietina, figured and 
named by Curtis, and which he first found at Amble- 
side ; it has since been found in the Grampians very con¬ 
siderably above the level of the sea, and it is thus essen¬ 
tially a northern species both from altitude and locality. 
It would appear that this species selects some flat stone 
of about a foot in surface, lying upon the ground over 
a hollow spot. Such a specimen, sent to the British 
Museum, had attached to its under side two hundred and 
thirty cocoons, indicative of a considerable colony, or 
perhaps the accumulation of successive years, as one- 
third of these cocoons were empty of tenants. These, in 
their new depository, continued developing themselves 
in the perfect state between March and June, males ap¬ 
pearing first. When the transformations of the season 
ceased, five-and-thirty were still left to present them¬ 
selves another year, and the following spring these were 
developed; thus, including those which had already 
escaped when the stone and its treasure was secured, 
three successive seasons were occupied in their trans¬ 
mutations. It may be a species that requires three 
years for its metamorphosis, and the whole deposit of 
cocoons may have been the result of three years* accu¬ 
mulative structure, the vital activity of their northern life 
being perhaps more sluggish than in species frequenting 
the south. The last species the 0. rufa , that in which 
the female is remarkable for its inverted horns, which 
