genera of some extent, and distributed over several countries, are in the same condition.
"What we have just stated, applies equally to the correlation of species with each other. If we take, for example, the genus Satyrus of Latreille, we perceive that it is composed of an infinite number of secondary groups, scarcely any of which are proper to one country. Thus, in Europe, we have the division to which Galatea belongs, extending along the basin of the Mediterranean, even into Persia; that of Hermione, which takes the same direction, and continues to Cachmere; that of Norna, proper to the polar regions of the two continents; that of Nigres, which inhabits mountainous countries, and is found only at the Cape and at Chili; finally, that of the Satyres, properly so called, which are connected with the species of New Holland, some of them with those of Chili, of North America, and Siberia. America and the East Indies, likewise, present groups which in general appearance differ widely from our European species; while there are others which resemble several at the same time. A collection of the Satyres of one country would, therefore, form a sufficiently natural series; but it would appear most irregular when the species of several countries were brought together.
"Our method is partly founded on the caterpillar, and partly on the perfect insect. We attach the greatest importance to the caterpillar state, and the characters which it furnishes have often more value
