Alan Cressler:
Aquirre Lake, Buenos Aires National Wildlife Refuge, Pima County, Arizona 1
Alan Cressler:
Asplenium palmeri, Sycamore Canyon, Pajarita Wilderness, Coronado National Forest, Santa Cruz County, Arizona 1
Alan Cressler:
Atascosa Peak, Atascosa Mountains, Coronado National Forest, Santa Cruz County, Arizona 1
Alan Cressler:
Baboquivari Peak, from Buenos Aires National Wildlife Refuge, Pima County, Arizona 1
Alan Cressler:
Calvary Cave, Fort Huachuca, U.S. Army, Cochise County, Arizona 1
Alan Cressler:
Calvary Cave, Fort Huachuca, U.S. Army, Cochise County, Arizona 1
Alan Cressler:
Carnegiea gigantea (crested), Paige Creek Canyon, Cochise County, Arizona 1
Alan Cressler:
Carnegiea gigantea, Saguaro National Park (east), Pima County, Arizona 1
Alan Cressler:
Carnegiea gigantea, Saguaro National Park (east), Pima County, Arizona 1
Alan Cressler:
Carnegiea gigantea, Saguaro National Park, Pima County, Arizona 1
Alan Cressler:
Carnegiea gigantea, Saguaro National Park, Pima County, Arizona 2
Alan Cressler:
Clear Creek Falls, Grand Canyon National Park, Coconico County, Arizona 1
Alan Cressler:
Colorado River, Marble Canyon, from Navajo Bridge, Grand Canyon National Park, Coconino County, Arizona 1
Alan Cressler:
Crotalus atrox, Rattlesnake Cove Cave, BLM Lands, Cochise County, Arizona 1
Alan Cressler:
Crotalus atrox, Rattlesnake Cove Cave, BLM Lands, Cochise County, Arizona 2
Alan Cressler:
Crotalus atrox, Rattlesnake Cove Cave, BLM Lands, Cochise County, Arizona 3
Alan Cressler:
Crotalus mitchellii pyrrhus, Mount Nutt Wilderness, BLM Lands, Mohave County, Arizona 2
Alan Cressler:
Crotalus mitchellii pyrrhus, Mount Nutt Wilderness, BLM Lands, Mohave County, Arizona 1
Alan Cressler:
Cylindropuntia acanthocarpa, Saguaro National Park, Tuscon Mountains District, Red Hills Area, Pima County, Arizona 2
Alan Cressler:
Cylindropuntia acanthocarpa, Saguaro National Park, Tuscon Mountains District, Red Hills Area, Pima County, Arizona 1
Alan Cressler:
Dantes Descent, Coconino County, Arizona, Brent Aulenbach 1
Alan Cressler:
Deadman's Cave, Pima County, Arizona, Jason Ballensky and Philip Rykwalder 1
Alan Cressler:
Dinosaur Tracks, Late Triassic to early Jurassic, Navajo Sandstone, Moenkopi Dinosaur Tracks, Navajo Reservation, near Tuba City, Coconino County, Arizona 1
Alan Cressler:
Dinosaur Tracks, Late Triassic to early Jurassic, Navajo Sandstone, Moenkopi Dinosaur Tracks, Navajo Reservation, near Tuba City, Coconino County, Arizona, Brent Aulenbach 1
Alan Cressler:
Echinocereus engelmannii, Saguaro National Park, Tuscon Mountains District, Red Hills Area, Pima County, Arizona 1
Alan Cressler:
Echinocereus rigidissimus, Alan Cressler's Cactus Collection, Tucson, Pima County, Arizona 1
Alan Cressler:
Echinocereus coccineus subsp. santaritensis, Madera Canyon, Santa Rita Mountains, Coronado National Forest, Santa Cruz County, Arizona 1
Alan Cressler:
Elves Chasm, Grand Canyon National Park, Coconino County, Arizona 1
Alan Cressler:
Lower Elves Chasm, Grand Canyon National Park, Coconino County, Arizona 1
Alan Cressler:
Elves Chasm, Lower Pool, Grand Canyon National Park, Coconino County, Arizona 1
