What is the name of that cruciform constellation?

Answer 1

Near the end of Fall, Cygnus points down (neck and head towards the NW horizon) for observers in moderate northern latitudes. In this configuration, it is known as the Northern Cross in many European cultures.

The Southern Cross is a cruciform constellation in the Southern hemisphere (visible from as far north as Hawaii and Barbados, for example).

There are also 'asterisms' (forms that are not constellations, like the Big Dipper) that look like crosses. The best known is called the False Cross. It is made from bright stars in Carina (the Ship's keel) and in Vela (the Sail); it is larger than the real Southern Cross and rises a few hours before the real Southern Cross.

For navigators going southward, eager to see the Southern Cross (because it points due south), they had to be careful not to be fooled by the False Cross. Once both crosses are above the horizon, it is easy to tell the real Southern Cross from the false one.

Answer 2

Southern Cross

Answer 3

Actually there are two: Crux (the Southern Cross) in the southern sky and Cygnus (the Northern Cross) in the northern sky. I'm not sure which one you're referring to, though.

Answer 4

Do you mean the Southern Cross that is also pictured on the national flag of New Zealand?
It is only visible when you are on the southern hemisphere (below the equator).

Answer 5

Cygnus the Swan