  We study the perturbative QCD description of the HERA measurements of $F_2
(x, Q^2)$ using a gluon distribution that is obtained from an evolution
incorporating angular ordering of the gluon emissions, and which embodies both
GLAP and BFKL dynamics. We compare the predictions with recent HERA data for
$F_2$. We present estimates of the charm component $F_2^c (x, Q^2)$ and of $F_L
(x, Q^2)$.
