no. 108 is spiritomb, who i think you find when fighting the elite four.
and 150 is palkia, once you beat the E4, go to the elder lady in celestic town and she will show you a picture of palkia, and then you can get the NATIONAL DEX! dun dun duun
hope ive helped
if you havent beat the elite four, i advise you do so, as you cannot find these two pokemon without beating them.