Serpens

Serpens (the snake) is one of the 88 modern constellations, and was also one of the 48 listed by Ptolemy. Among the modern constellations it is unique in being split into two pieces, Serpens Caput (representing the head of the snake) and Serpens Cauda (representing the tail). Between these two pieces lies the constellation of Ophiuchus, the serpent bearer.