This method is passed a readable handle from which it reads a list of Bio::Phylo::Matrices::Matrix objects. It uses the Bio::Phylo::IO::parse function, which needs among its parameters a -format flag that specifies the syntax format. The value for this flag is obtained by taking the last part of the child class's package name. The optional third argument specifies the datatype. The default for this argument is 'dna', but 'rna', 'protein', 'standard' and 'continuous' may also be used.