Undo Split

In the Montage you can split all the tracks in the edit menu. How do you, without undoing everything, later remove a split no longer required, or in my case placed in error? Is there an equivalent of the Cubase glue command?

Surely this cant be to hard?

Unless this is your last action, in which case you can of course use the traditionnal undo command, there is no specific glue action. But you can simulate it by deleting the right part and resizing / extending the left part to the right.