  In this note we discuss the theory of super-threebranes in a spacetime of
signature (10,2). Upon reduction, the threebrane provides us with the classical
representations of the M-2-brane and the type IIB superstring. Many features of
the original super (2+2)-brane theory are clarified. In particular, the (10,2)
superspace and the spinors required to construct the brane action are
discussed.
