Rarely has nature seemed more fragile than it does in E.W. Ross's 53 small landscape drawings at the Chicago Cultural Center, which resemble tiny, dreamlike dioramas. In The Frog's Agony, a dying creature perched on a branch recalls the recent massive dying off of frogs around the world--a possible sign of looming ecological catastrophe. But the drawing is gentle, romantic, not at all preachy: Ross carefully renders tree bark in pencil and uses watercolor to add sensuality. Some images are a bit surreal, like one showing a prosthetic foot in a forest. The chair in Wheelchair in Landscape #2 (Nod to Seurat) is dwarfed by the surrounding trees yet so precisely outlined, every spoke visible, that it suggests the power of human intrusion, however benign; uneven swaths of tan and blue green give the tree trunks and forest ground a floating, almost weightless feel. Throughout the exhibit Ross's mix of Durer-like precision and airy watercolor creates a fine tension between the world as it is and flights of fancy, and he often makes incongruous man-made elements--like a tiny traffic light hanging among trees--seem signs of ego in places where it doesn't belong. Chicago Cultural Center, 78 E. Washington, through October 27. Hours are 10 to 7 Monday through Wednesday, 10 to 9 Thursday, 10 to 6 Friday, 10 to 5 Saturday, and 11 to 5 Sunday; 312-744-6630 or 312-346-3278.