Herewith a reminder of Simon Banton's wonderful web/blog site, on which he has photos of all of the visible Stonehenge stones. Quite a catalogue -- and since we last reported, there are many new images. Thoroughly recommended!
According to Simon, these are the missing stones:
Some bluestones and bluestone fragments that are labelled on the plan, for example Stones 32c (Type: Altered Volcanic Ash), 32d (Type: Spotted Dolerite), 32e (Type: Rhyolite), 33e (Type: Altered Volcanic Ash), 33f (Type: Altered Volcanic Ash), 40c (Type: Calcareous Ash), 41d (Type: Altered Volcanic Ash), 42c (Type: Sandstone with Mica), 70a (Type: Spotted Dolerite), 70b (Type: Unknown) and 71 (Type: Unknown), do not have pictures or pages because they are not visible above ground level and exist only as completely buried stumps.