function createAuction(uint40 _cutieId, uint128 _startPrice, uint128 _endPrice, uint40 _duration, address _seller)
        public whenNotPaused payable
    {
        require(_isOwner(msg.sender, _cutieId));
        _escrow(msg.sender, _cutieId);
        Auction memory auction = Auction(
            _startPrice,
            _endPrice,
            _seller,
            _duration,
            uint40(now),
            uint128(msg.value)
        );
        _addAuction(_cutieId, auction);
    }