Fig. 2. Relative values (mean ± S.E.M.) of shell, shell water,
shell ash and shell organic content of hatchling Chelydra serpentina,
Chrysemys picta and Graptemys geographica, and adult
Chrysemys pict. Different symbols indicate a significant difference
among species. Sample sizes are listed above the bars. Data for adult
Chrysemys picta (% shell) are from Jackson et al.
(1996) and shell composition
from Jackson et al.
(2000).