According to legend, what did constantine see in a vision on the night before his most impressive military victory?

According to legend Constantine saw a vision flaming cross in the sky.

People say that he saw a sign of Jesus. Most agree that it was the cross, but some say it was a sword, ect. 
So to answer your question: It was the cross. 

Mexico has a host of environmental problems, including significant chemicalpollution  from factory discharges and waste dumping, but the main threat to itsbiodiversity  probably stems from  deforestation  and other natural habitat losses. forest habitat is lost for a number of reasons