After Uninstalling Windows, upon boot I get "No Readable Device," Only can boot w/ALT

Hi guys.

I originally uninstalled windows using bootcamp, and gave all the space back to Mac OS X. About 4 hours later I decided I wanted to reinstall it (no comments please). Then in the middle of the reinstall I decided that I actually don't want it, and went back into Mac OS X and restored it, deleting Windows with boot camp.

Now, everytime I boot the screen stays white for a long period of time, then it goes black and in a console looking grey font it says "No readable device to boot from."

Now when I hold alt at bootup and manually press Macintosh HD everything boots up fine.

Thanks in advance.

(If you think I need to do a reinstall thats fine, because I have everything backed up via Time Machine.)

 

Thanks lol, selecting OSX as startup worked.

Yeah I have trouble making my mind up on small decisions like which OS to run on my MBP. Then life changing decisions come easy to me >_>. Thanks!