R. Zweifel Calloscure decemlira Isla Chapalra, W of Nueces, Texas Mexico April 25 A low, rounded island with a relatively sparse growth of dry herbaceous vegetation and a few cholla. The soil is a little of water-worn, rounded pebbles about 1" in diameter. There are, large rocks 1" in cross diameter scattered about. These lizards were very abundant. Thirteen were secured in about 45 minutes, 8 shot and four captured alive. Here they were relatively easy to capture by hand, since they could often be run until they tired and then would easily be captured. They seemed to be most abundant on the beach, but were present over the whole island.