Jack,
More simply put (I like simple), most typical transmissions send the power shaft out the back. In a rear mid engine car, typically the transaxle (incorporating the TRANSmission and the rearAXLE) sends the power out the sides. The benefit of this is to reduce weight and overall length. The center of the black parts in the photo that Mark (DEVIL) posted are where the driveshafts are attached (and what rotates to drive the wheels).
Mark
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