Mystery flower

A tree in Llano Park is loaded with these beautiful white flowers, but as yet I don't know the name of it. I also thought the position of the leaves on the branches was interesting, and I couldn't decide, so I put it here

I have a book called "Tropical Flowering Plants" that is a guide to ID and cultivation. However, it has 400 pages and is organized by Latin names, so in order to ID a plant, you have to look through the entire book and try to find a picture that looks like it. This takes some time!!!

In all my times in Mexico, I have not had much success asking people plant names. A guide who sometimes goes on the Friday hikes with us knows a lot of local plants, so I will send him a photo and maybe he can answer. Maybe one of you knows???