C++ - compilation error

I am implementing a vector, and for some reason, my header file keeps saying this error:

error C2590: 'CopyValues' : only a constructor can have a base/member initializer list see reference to class template instantiation 'Vector<T>' being compiled error C2533: 'Vector<T>' : constructors not allowed a return type error C2760: syntax error : expected '{' not ';' error C4430: missing type specifier - int assumed. Note: C++ does not support default-int error C2039: 'GetNewCapacity' : is not a member of 'Vector<T>' 

Here's my header:

template <class T> class Vector { public: typedef T* Iterator; Vector(HeapAllocator* allocator); Vector(HeapAllocator* allocator, size_t size); ~Vector(); size_t capacity(); size_t size(); bool empty(); void clear(); Iterator insert(Iterator position, const T& value); void insert(Iterator position,size_t n, const T& value); void insert(Iterator position,Iterator first, Iterator last); void erase(); void resize(size_t numElements); void push_back(const T& item); void pop_back(); private: void CopyValues(Iterator pBegin, Iterator pEnd, Iterator pTarget): // when I comment out this method, it compiles fine, why? size_t GetNewCapacity(size_t currentCapacity); T* mBegin; T* mEnd; T* mCapacity; HeapAllocator* mAllocator; }; 

Im staring blindly at the code, but I can't find any syntax error. What is causing this?