Click the top curve of the leg. Now click on the edge curve of the body where the sphere spilt it. You will see that the whole edge did not select. You must select each part of the edge until you have all of the edge selected. When you see the arrows, Press Enter.
Lets have a look.
If you like the way the blend looks, it's time to move on. If you don't like the way the blend looks, Go back and redo the Sphere split. Turn on Body, Arm and Leg layers. Select all of the surfaces you made. Now lets mirror this half body.