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that in general terrapins grow rather rapidly during the first 5 or 6 years, followed 
by a much slower growth, and after an age of 8 to 10 years is attained growth is so 
slow that it is almost negligible. 
The males in all broods of Carolina terrapins grown to maturity have been 
greatly in the minority. This disproportionate sex ratio has existed in unselected 
lots as well as in selected ones. A ratio of 1 male to 6.4 females exists among the 
Carolina terrapins grown in captivity. In certain hybrid lots (crosses between 
Carolina and Texas terrapins) the males are much more numerous. Since the lots 
are small ones, this greater proportion of males may have no significance. If the 
usual 1-to-l sex ratio exists in young terrapins (which has not been determined), 
then it apparently would have to be assumed that the males are less resistant to 
life in captivity than the females, and they simply fail to reach maturity. This 
supposition does not appear to be tenable, however, because the number of deaths 
in some of the lots was too few, even if males only had died, to make a ratio of 1 to 1. 
BIBLIOGRAPHY 
Barney, R. L. 
1922. Further notes on the natural history and artificial propagation of the diamond-back 
terrapin. Bulletin, U. S. Bureau of Fisheries, Vol. XXXVIII, 1921-1922 (1923), pp. 
91-111, figs. 76-84. Bureau of Fisheries Document No. 917. Washington. 
Coker, R. E. 
1906. The natural history and cultivation of the diamond-back terrapin, with notes on other 
forms of turtles. North Carolina Geological Survey, Bulletin No. 14, 1906, 69 pp., 
XXIII Pis. Raleigh. 
Hay, William Perry. 
1905. A revision of Malaclemmys, a genus of turtles. Bulletin, U. S. Bureau of Fisheries, 
Vol. XXIV, 1904 (1905), pp. 1-20, Pis. I-XII. Washington. 
1917. Artificial propagation of the diamond-back terrapin. U. S. Bureau of Fisheries 
Economic Circular No. 5, revised, 1917, 21 pp., 5 figs. Washington. 
Hay, W. P., and H. D. Aller. 
1913. Artificial propagation of the diamond-back terrapin. U. S. Bureau of Fisheries 
Economic Circular No. 5, 1913, 14 pp., 3 figs. Washington. 
Hildebrand, Samuel F., and Charles Hatsel. 
1926. Diamond-back terrapin culture at Beaufort, N. C. U. S. Bureau of Fisheries Economic 
Circular No. 60, 1926, 20 pp., 8 figs. Washington. 
Stejeneger, Leonhard, and Thomas Barbour. 
1923. Check list of North American amphibians and reptiles. Ed. II, 1923, 171 pp. Harvard 
Univ. Press, Cambridge. [Malaclemmys, pp. 131-132.) 
