Many aphides, &c., puncture the leaves, suck out the sap, and induce va:ious local deformations, arrest of growth, pustular swellings, &c., and if numerous all the evils of defoliation may follow.
Similarly with Anemone infested with Puccinia and Vacciniusn with Catyptospora, and many other cases of deformations due to hypertrophy or atrophy.
A great variety of deformations and growths produced by insects and mites as well as by fungi have been described.
Trend to crustal deformations which in very early geological time gave a beginning to what later came to be the Appalachian mountain system; but this system had Its climax of deformation so long ago (probably in Permian time) that it has since then been very generally reduced to moderate or low relief, and owes its present altitude either to renewed elevations along the earlier lines or to the survival of the most resistant rocks as residual mountains.
The Pacific coast has been defined chiefly by relatively recent crustal deformations, and hence still preserves a greater relief than that of the Atlantic. The minor features of each coast will be mentioned in connection with the lani districts of which the coast-line is only the border.