Guys.. Some of you are being quite rude towards the depiction of
Hindu deities.. May I request that you do not assume things (e.g
calling the serpents Medusa) if you aren't sure about the
facts.
The Lion Deity picture: His name is Narasimha, the fourth
incarnation of major Hindu deity, Vishnu. Although a very benign
Deity, Vishnu assumed this fierce form, as the demon (whose name is
Hiranyakasibu) he is killing had obtained a very complex boon from
another God.
According to the boon, the demon could not be killed indoors or
outdoors, at dawn or at dusk, by man or by animal, by any man-made
weapons, on the ground or in the air.
Thus to kill him while honoring the boons, Vishnu took on a form
that was neither man or animal, He dragged the demon to the castles
entrance (neither indoors or outdoors), He placed the demon on His
lap (neither on ground or in the air), He waited for midnight
(neither day nor night) and killed him by ripping his torso using
His claws (not a man-made weapon)
The serpent (whose name is Sesha) at the background serves Vishnu
as His bed. And as someone posted earlier, Narasimha is worshipped
in the hindu temple at Waterloo Street.
The boy (not girl) in the picture, is the demon's son, Prahalada.
Unlike his father, Prahalada was a devotee to Vishnu, and was the
one who calmed Him down after He flew into a rage while killing the
demon.
Hope that helped to clear your queries on the picture 
