From the Khingan ranges to the Pacific, south of the Amur, stretch the rich districts of Manchuria, a province which connects Russia with the Korea by a series of valleys formed by the Sungari and its affluents - a land of hill and plain, forest and swamp, possessing a delightful climate, and vast undeveloped agricultural resources.
The mineral resources are undeveloped, but are said to include copper, gold and silver.
Foreign trade and foreign intercourse were undeveloped, but their influence was in historical times never entirely absent, while the influence of Roman law and the Christian Church constantly tended to modify the manorial organization.
The calculus of variations lay undeveloped in Euler's mode of treating isoperimetrical problems. The fruitful method, again, of the variation of elements was introduced by Euler, but adopted and perfected by Lagrange, who first recognized its supreme importance to the analytical investigation of the planetary movements.
The vast majority of individuals in a community consist of wingless forms - " workers " and " soldiers," which are undeveloped members of either sex.