Take a look at old postcards featuring fungi, and it's obvious that one species dominates: the fly agaric, or Amanita muscaria.
According to Tjakko Stijve, who wrote a fascinating article in Australasian Mycologist, (18:3:72) it is fairly evident that A. muscaria is a potent symbol of good luck.
He points out that even though many postcards feature Boletus edulis (a species not found in Australia, but have a look at this), most feature A muscaria as a love symbol - often we see lovers shielded by a huge A. muscaria cap.
Many such postcards were sent by young people in love. In the card from Wommels in the Netherlands the woman lets her lover know that she is 'afraid but willing.'
Some of the cards pictured here seem to suggest that Freud was right when he suggested that some fungi have a certain phallocentric resonance with the love-lorn imagination, but rarely has a fungi such as Phallus imodicus, whose shape is evocative enough, been used as source of inspiration.
Tim Birkhead in the Times Higher Education (http://www.timeshighereducation.co.uk/story.asp?storycode=405235) says that Darwins daughter, Etty, was so appalled by the suggestiveness of stinkhorns that in latter life she mounted a campaign to eradicate them 'because of [their] influence on the maids.'
Birkhead continues: "Now if you or I were to undertake such a campaign, we would simply squish the stinkhorns underfoot - a tad messy perhaps, because they are rather gelatinous, but by far the easiest way to destroy them. But Etty didn't do that. Instead, she picked them, brought them home in a napkin-covered basket and burnt them in the privacy of her study."