These faces are shown in greater detail in my main photograph, where you can see the complexity of the entire left hand of the monolith, below I have extracted the main elements as I see them:

Figure I

This majestic left profile face looks towards the east.   According to Professor Meaden left looking neolithic faces were intended to be feminine, and so this carving would represent a woman.   The cone shaped area above the face may represent some sort of headress?

My image here is intended to show the face in the context of other elements on the monolith, but it is unlikely the sculptor intended his/her work to be lit as I have done.   By contrast the image in Meadens' "Secrets" book (see p44) is lit by the sun as intended, and accordingly his image shows the face to be more subtle and nuanced than mine, my image here makes it look almost art deco, perhaps as it would have been seen at night lit by bonfires within the henge.

I believe that this "pristess" has a priest companion high on the southern/other side of the monolith and placed higher up, to see him click here.

Additionally the left profile female face shown here also has an exact counterpart on the southern elevation, showing that the sculptor envisaged this character to be a rounded one, see the comparison image immediately below -  convincing proof, if any were needed, that some of the Avebury faces have been carved by humans, they are not all accidents of nature.

Figure II

This rotated zenith-gazing face of a beast is my discovery and may well be partly carved, I talk about the importance of such faces at Avebury here.

Figure III

This quirky little face is clearly natural, a true simulacrum. However it could easily have been seen as an eerie bird's face. Although the feature is small, it is visually very striking, and I can't help speculating whether the scultptor has worked it into his/her design as almost sitting on the shoulder of the main left looking face (described in point A above).