Spittle tube with spittle

Description:

A 10 mm long calcareous spittle tube 'cemented' along a flower bud. Seen at the tube opening was some spittle.

Habitat:

Spotted on a eucalytpus tree.

Notes:

This tree had several tubes and even a small spittlebug resting near a tube like this one
http://www.projectnoah.org/spottings/169...
The family Machaerotidae are spittle bugs that make tubes out of calcium carbonate (75%) stuck to wood parts of plants. The nymphs of the bugs live inside these tubes in a clear fluid secreted by them.
I have never seen one with foam out of the tube, the foamy spittle (cuckoo spit) is often seen in the other family of spittle bugs and the spit is seen on branches or leaves with nymphs hidden inside the foamy mass.