
Common name: Dita bark, Devil tree, Blackboard tree, Milkwood pine
Native to India and SE Asia. Commonly believed to be the abode of the Devil! And in some villages, people are afraid to sit under this tree.
The botanical name Alstonia scholaris is interesting. Alstonia to honour a great botanist Prof. C Alston, and Scholaris because it’s wood is traditionally been used to make wooden slates for children.
In October, the greenish fragrant flowers appear.
The bark constituents were considered an alternative for treatment of malaria.
Whether it is an abode of the devil or not, it is a beautiful tree even when not flowering. 
Botanical name: Alstonia scholaris Family: Apocynaceae (oleander family)
Info – Flowersofindia.net, Wiki
Picture taken at Necklace Road, Hyderabad.