22 Trans. Acad. Sci. of St. Louis 
which was obtained from the examination of the 55 speci- 
mens of S. undulatus undulatus and the 108 specimens of 
S. undulatus thayerii, does indicate a difference in the 
proportions of the two lizards. 
undulatus thayeru 
Mode of width of head as per- 
centage of body length_- 18- 20 16- 18 
Mode of total length in mm. 91-105 111-120 
It is apparent that the series of S. undulatus undulatus 
are on the average about 18 mm. shorter than the series 
of S. undulatus thayerii, and that the width of head as 
percentage of body length in the former lizard averages 
two millimeters greater than in the latter form. Hence, 
these data indicate a wider head in proportion to the 
body length for the subspecies S. undulatus wndulatus, 
and conversely, a more slender body when compared 
with the width of head for the subspecies, 8. undulatus 
thayerit. 
So far as known, the measurements given by other 
writers for the pine lizard agree with those of the author. 
Habitat and Habits—Considerable mention has been 
given the pine lizard in the literature, because its wide- 
spread distribution has enabled many American natural- 
ists to study it. De Kay (1842) stated that ‘‘It inhabits 
sandy and rocky situations.’’ Holbrook (1842) wrote 
that ‘‘It is chiefly found in the pine forests of our coun- 
try, being often under the bark of decaying trees. It 
chooses old fences as a basking place. It is exceedingly 
rapid in its motions, climbing with great facility to the 
tops of trees, and hence it is not taken alive without 
great difficulty.’’? Smith (1882) wrote that ‘‘It prefers 
sandy and rocky soils, especially regions of pine forests, 
and apparently does not occur in wet places.’? Hay 
(1892) stated that ‘‘It is not disposed to seek safety by 
