S Sand cricket 36-37 _Scolopendra heros_ 3 Scorpions 4-7 Sidewinder 26-27 Solpugid 36 _Sonora_ 30 Sonoran Desert Frontispiece _Sphecidae_ 17 Spiders 7-14 _Stenopelmatus_ 36-37 Striped-tail scorpion 4 Slender-tail scorpion 4 Squash bug 14 T _Tantilla_ 30 Tarantula 13-14 _Triatoma_ 14 _Trimorphodon_ 30 _Trithyreus_ 37 V _Vejovis spinigeris_ 4 Velvet ant 17-18 _Vespidae_ 17 Vinegaroon 37-38 W Walpai tiger 14 Wasps 17, 19 Western diamondback rattlesnake 25 Whip-tail scorpion 37 Y Yellowjackets 19 This booklet is published in cooperation with the National Park Service by the SOUTHWEST PARKS AND MONUMENTS ASSOCIATION _a non-profit distributing organization pledged to aid in preservation and interpretation of Southwestern features of outstanding national interest_. The Association lists for sale many excellent publications for adults and children and hundreds of color slides on Southwestern subjects. We recommend the following items for additional information on the Southwest and the National Park System: