  We generalize recent results of Haas and Miermont to obtain scaling limits of
Markov branching trees whose size is specified by the number of nodes whose
out-degree lies in a given set. We then show that this implies that the scaling
limit of finite variance Galton-Watson trees condition on the number of nodes
whose out-degree lies in a given set is the Brownian continuum random tree. The
key to this is a generalization of the classical Otter-Dwass formula.
