5: Model-builder's activity
22: Pooch in 'The Wizard of Oz'
23: Copy editor's quarries
25: Blended-family prefix
28: They're passed on from father to son
30: Ferris wheel and roller coaster
37: Triangular sail insert
44: More dry and withered
45: 'The Gift of the Magi' device
49: Old-time telephone feature
50: Type of belly and barrel
54: Helios, to the Romans