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.