Equuleus, the Little Horse, is a constellation that lies between Pegasus and Delphinus. Equuleus is thought to be Cerleris, the swift brother of Pegasus, whom Mercury gave to Castor, the brother of Pollux (Gemini). Or it could be Cyllarus, whom Juno gave to Pollux. In any case, it can be seen rising in mid-September just before Pegasus.
