My understanding of the positions are:
Front stretch - both hands on the foot, leg in front of the body like a split
Heel stretch - the foot/leg completing a high V with shoelaces facing to the back
Bow - leg coming up along the side of the body like a centre split
Arabesque - chest lifted, shoulders faced more forwards, hips simultaneously facing the front and the audience side lifted (much to the horror of my ballet years) with the active leg turned out so shoelaces face to the audience
Scorpion - knee and shoelaces facing to the back, torso faced to the front, with the legs like a split leant back into evenly (irrespective of bend in the leg or not)
Scale - hip open to the front, shoulders facing to the front and I'm blanking on the foot :eek:
Of course these are theoretical goals generally, what I end up doing is... different...
Also, the foot never sickles so the leg and foot continue in a straight line.