The LSB from this byte is the R/W bit and has nothing to do with the adress off the device. You do have to send it though..
It has everything to do with the address value that you send to a library that expects an 8 bit address.
Lets see you use the wire library beginning with the transmission of a 7 bit address followed by the transmission of a single read/write bit.
The device DOESN'T expect an 8 bit adress. It expects a BYTE. This byte is made up of the 7 MS bits which determines the device adress and the lsb which indictates wether you are writing or reading to/from the device.
So if you want to write
to the device 0x38, the first byte you (or rather the wire-library) send is b01110000
(0x70). For reading
the same device you send b0111001
I may not know the wire library inside out, but I sure know how to read and interpret a datasheet..