Lactarius s.l. (A Milkcap)

The fruit bodies of Lactarius are mushrooms that grow on soil. They come in a variety of sizes, shapes and colours. 

Species of Lactarius are commonly known as Milkcaps and the generic name is derived from the Latin word for milk. When damaged, Lactarius tissue exudes a fluid, white being the most common colour. In this photo (http://www.cpbr.gov.au/fungi/images-captions/lactarius-sp-0003.html) you see two Lactarius mushrooms, one lying on its side. There are white droplets on the gills of the latter. Before taking that photograph I had pressed a fingernail against the gills and damaged some of them, which caused a milky juice to ooze out from the damaged tissue. Lactarius is not the only fungal genus in which such bleeding occurs, but the phenomenon is found in only a small number of genera and so, when you see it, you immediately know that you have very few genera to consider.  

Usually, when you try to snap a mushroom stem, you don't break it clean through, though you may break it in part, but mostly it bends with little breakage. By contrast a Lactarius stem snaps cleanly. That is also one characteristic of the mushroom-producing genus Russula, but species of Russula don't bleed. One warning: the snapping of the stem shows best in mushrooms in prime condition. If a mushroom has started shrivelling the breakage need not be so dramatic. Some field guides compare an attempt at breaking a typical mushroom stem to breaking a stick of celery and an attempt at breaking a Lactarius (or Russula) stem to the breaking of a stick of chalk. A stick of celery may break to some degree, but usually the two sections are still connected by at least some fibres.   

The spore print is white to cream.

Lactarius is a mycorrhizal genus. A number of native species are found in native forests or woodlands but there likely to be more, as yet undescribed, native species and some introduced species are found in association with exotic plants in our area.

Recent molecular work has led to the splitting of the genus Lactarius into several genera. However, for visual identification it is best to use Lactarius in the broader, older sense and so you see Lactarius s.l., that last pair of letters being the standard abbreviation in botanical works for the Latin phrase sensu lato (meaning 'in the broad sense').