Cecchetti Arabesques vs. Vaganova Arabesques

The Cecchetti method uses five principle arabesques while the Vaganova method uses four.

The Cecchetti Arabesques
First Arabesque: The body is held upright and supported on a straight leg with the other leg extended and at right angles supporting the leg. The shoulders are held square to the line of direction with the arms extended, palms down, so that the fingertips of the forward arm (the same side as the supporting leg) are in a line with the center of the space between the eyes, and the extended back arm slightly lowered so that the arms are in one straight line. The forward hand should be slightly turned outward.
Second Arabesque: The arms are reversed so that the forward arm is the opposite to the supporting leg. The head is slightly inclined and turned towards the audience.
Third Arabesque: Both arms are extended forward to the side of the supporting leg. The fingertips of the arm farther from the audience are in line with the center of the space between the eyes while the arm nearer the audience is in a line with the shoulder.
Fourth Arabesque: The supporting leg is nearer the audience and is in demi-plié. The arms and head are held as in the first arabesque with the arm on the side of the raised leg being forward.
Fifth Arabesque: The arms and head are held as in the third arabesque with the arm farther from the audience being the higher. The supporting leg is the leg nearer the audience and is in demi-plié.
The fourth and fifth arabesques are usually taken facing the right front corner of the room or stage if the supporting leg is the left, or facing the left front corner if the supporting leg is the right.

The Vaganova Arabesques
First Arabesque: The body is supported on one leg with the other lifted at a right or greater angle to the supporting leg. The body is inclined forward from the waist with a strongly arched back. The arm on the side of the supporting leg is extended forward and the other taken out to the side a little behind the second position.
Second Arabesque: The body and legs are the same as in the first arabesque but the arms are reversed. That is, the arm on the side of the supporting leg is taken back far enough to be seen behind the body while the other arm is extended forward. The head is turned toward the audience.
Third Arabesque: Faces diagonally towards the audience. The supporting leg is nearer the audience with the other raised in croisé derriére at right angles to the supporting leg. The body is inclined forward with the arm opposite the supporting leg extended forward on a level with the shoulder and the other arm extended to the side. The head is turned towards the forward arm.
Fourth Arabesque: The legs are in the same position as in the third arabesque but the arms are reversed and held at shoulder level. The arm on the side of the supporting leg is brought forward and the other arm is taken back far enough to be seen behind the back. The body is half turned away from the audience by the strong arching of the back, with the head turned towards the audience.

Grant, Gail. Technical Manual and Dictionary of Classical Ballet. New York: Dover Publications, 1967. 2-3. Print.