The cyanobacterium Oscillatoria animalis is a very social bacterium that forms complex multicellular and gas filled bodies that allow it to float on the surface of water.

A gas filled multicellular body formed by Oscillatoria

In order to propagate these bodies, I cut the one above into two, and separated the two daughter forms on the surface of liquid media (see the image below)

The two newly split daughter forms

I left the two forms for two days before I observed them again but when I did, I found that not only had they healed themselves, but they had reached out across 10 cm of space to reconnect with each other (see the image below)

Reconnection of the two forms across 10 cm of liquid culture

Over the following week the two once separate forms,  gradually pulled themselves together and finally reunited once again (see the following images)

Reunion