What is the difference in the meaning between the lengths of lines in a phylogram and ultrametric tree?

A phylogram is a phylogenetic tree where edge lengths signify time or genetic distance while an ultrametric tree or "chronogram" is a phylogenetic tree where edge lengths represent time. Also i n an ultrametric tree, all tips of the tree are equidistant from the root of the tree. While a phylogram has dissimilar branch lengths which quantitatively signify the opposing degrees of change between the root and each terminal node.