c++11: std::bind for sub-class member-functions

i'd like to invoke runtime-bound functions of classes, that inherit a binding ability from a common class "Bindable". Is that actually possible?

Here's a stub which surely lacks a lot of template-arguments and namespaces:

#include <iostream>     // std::cout
#include <functional>   // std::bind
#include <map>          // std::map

class Bindable {
public:
    void bindFunction (int x, auto newFn) {
        mFns.insert(std::pair<int, auto>(x,newFn));
    }
    void invokeFunction (int key) {
        mFns.at(key)();
    }

protected:
    std::map<int, function> mFns;
};

class A : Bindable {
    void funAone (void) {
        cout << "called funAone" <<std::endl;
    }
    void funAtwo (void) {
        cout << "called funAtwo" <<std::endl;
    }
};

class B : Bindable {
    void funBone (void) {
        cout << "called funBone" <<std::endl;
    }
    void funBtwo (void) {
        cout << "called funBtwo" <<std::endl;
    }
};

int main() {
    A a;
    B b;

    a.bindFunction(1, &A::funAone);
    a.bindFunction(2, &A::funAtwo);
    b.bindFunction(1, &B::funBone);
    b.bindFunction(2, &B::funBtwo);

    a.invokeFunction(1);
    a.invokeFunction(2);
    b.invokeFunction(1);
    b.invokeFunction(2);
}