I had the opportunity to go walking up the back in the bush yesterday. The sun reflected off an object laying on the ground which seemed vivid green. Seeking this, I found a leaf covered with a cluster of large spherical attachments – too large for eggs, so presume they must be some kind of cocoon. At first I thought they might be Gall Wasp cases, but in my experience, Gall Wasp cases are odd shapes, not uniform as these are. Gall Wasp casings also have a harder exterior, often with small holes. The unidentified cases were smooth when I found them, slightly more wrinkled this morning. Picking up the leaf, it feels heavy, so I assume there is larvae still inside each one.
Can anyone tell me what they might be? I’ve included a 5 cent coin in the photograph as a way of indicating scale.
Fifteen Acres 
Definitely galls. Notice the small holes where they adults have escaped? We get them on Coast wattles, but they are more ‘potato’ shaped than spherical. You must have very neat and tidy wasps!
Thanks Rob. The bottom image is Gall Wasp and was photographed a year or so ago. The texture of the new ones was very different, so I’m not sure. However, I can’t think of anything else that would fit the description – not that I know much about insects! Thanks for your thoughts. Lisa