2 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 125 
As a result of the observations made in conjunction with other field 
studies, the authors have collected considerable information about 
the natural history of lizards in the vicinity of Belém, Para, Brazil. 
Some of this has already been published (Rand, 1965; Rand and 
Rand, 1966), and additional papers are planned. In this paper we 
present our data on microdistribution patterns among the common 
diurnal lizard species and its relevance to possible interspecific com- 
petition among lizards. We also present our data on lizard body 
temperature and their relation to habitat distribution. 
The senior author, who has made four trips to Belém, has spent 
a cumulative total of almost four months there between 1963 and 
1966. These visits were all made during the period of May through 
August, a time of intermediate rainfall. The junior author visited 
Belém from July through August, 1964, and from June through 
August, 1965. 
The observations reported herein were made in the vicinity of the 
city of Belém, Par4, at lat. 1°27’S, long. 48°30’W, altitude less than 
100 feet. The climate is hot tropical with abundant rain and a marked 
but not severe or prolonged dry season in the southern winter. The 
climax vegetation is forest, of which three types are locally recog- 
nized: “mata de terra firme” or upland forest; “varzea” or forest that 
is flooded daily by the freshwater tides; and “igapo” or permanently 
flooded swamp forest (Ducke and Black, 1953). We were able to 
sample the first two forests much more adequately than the latter. 
In addition to the above, we visited a variety of sites that had been 
disturbed by man and were in various stages of regeneration—from 
scattered bunches of grass and bare ground to old second growth. 
The main localities where our observations were made are as follows: 
Parque do Museu Goeldi — a small patch of forest in the city, 
the undergrowth much modified and denser than normal because of 
edge effect in some places, cleaned out in others, but the canopy only 
slightly disturbed. 
Bosque Municipal — a somewhat larger but still small patch of 
forest in the city, modified in much the same way as the Parque do 
Museu, but less so. 
Utinga and Agua Preta — localities in the preserve around the 
city water supply on the edge of the city, which include “mata de 
terra firme,” selectively cut but quite good in places, and various ages of 
second growth from just abandoned “rocas” through dense tangles to 
forest that betrays its second growth nature only in the species 
composition. 
IPEAN and Guama Forest Reserve — localities of “mata de 
terra firme,” “varzea” and some “igapo” forest. A variety of ages of 
