PARIS — You walk through a garden lush with overgrowth, a cultivated wilderness with exotic grasses gone deliberately to seed. Inside the effect is the same: You enter the eerily atmospheric hall where you meander past artifacts from Oceania, Africa and other realms beyond Europe’s borders, as speckled daylight seeps through window scrims decorated with forest foliage. The displays are lush with miscellany: here, an ivory statuette of a goddess from the Tonga islands that once was shown in an 18th-century curiosity cabinet; there, a desiccated human skull, covered in black-colored beeswax, acquired in early-20th-century Papua New Guinea.

But wait: before trying to decipher this strange universe, at the Musée du Quai Branly, consider another, elsewhere in Paris. Only here the impression is of vast, arching spaces and skylights that cast no shadows. You readily recognize the iconography of church portals, pilasters and statuary. It looks as if entire facades had been amputated from cathedrals all over France in a wild species of plunder. Here are the intricately ornamented arches of a 12th-century church in Saintes; there, ornate 16th-century doors from the cathedral of Aix-en-Provence. Centuries of grotesque, open-mouthed gargoyles are poised on a wall overhead, as if prepared to spew venomous rainwater.

You gaze in wonder at what seems to be intricately carved and worn stone. But, more remarkably, everything is made of plaster. It is a hall of casts chronicling some 700 years of French architecture on the ground floor of the Cité de l’Architecture et du Patrimoine.

Could two museums be more different? Both were unveiled during the last decade (the Quai Branly in 2006, the Patrimoine in 2007). Both evolved out of older collections and defunct institutions. But one displays authentic artifacts, the other reproductions; one focuses on non-Western cultures, the other on a quintessentially Western culture. One takes whole objects out of context, essentially turning them into fragments, while the other takes fragments out of context, essentially treating them as whole objects.