BLOOD VALUES IN SOUTH-AMERICAN LIZARDS FROM HIGH AND LOW ALTITUDES

1. Blood indices were measured in 27 species of lizard from Chile and Argentina occurring at different altitudes ranging from sea-level up t o 4600 m. 2. Contrary to amphibians, none of the hematological values of these lizards, such as hematocrit, hemoglobin concentration, red ce ll count, mean cell volume, mean cell hemoglobin and mean cell hemoglo bin concentration, were found to be correlated with their altitudinal distribution. 3. Intrageneric comparison of blood values in Liolaemus lizards (seven highland species living above 3000 m and 12 lowland spe cies) showed a similar degree of independence from their altitudinal s ite of capture or from their upper limit of distribution. 4. As report ed for other vertebrate taxa, an inverse correlation between size and number of red blood cells was also found in the studied reptiles.