Some may question why some innocuous animals are included here. Well, who's to say whether some DM wants to have his players' characters step on a poisonous urchin spine, or be subject to a mutant, nostril-seeking brain worm...
"As a general rule I dislike faffing about with fiddly bits intensely..." -Catweazle
"It sucked so bad that black holes across the universe went, 'Damn, that sucked!'" -Mock26