

10 BULLETIN OF THE BUREAU OF FISHERIES. 



1896. Bangs, Odtram. — Procceedings Boston Society of Natural History, XXVII, 159-161, Oct., 1896. 



Records the occurrence of M. terrapin in the headwaters of Buzzards Bay, at Eastham, on Cape Cod. 

 " After careful study we came to the conclusion that the terrapin from the whole Atlantic coast is one 

 species. It is subject to the most extraordinary range of individual variations, however, not only in 

 color, markings, and roughness of shell, but in the more important structural features, such as size and 

 shape of skull, of the horny portions of the mouth and the alveolar region. All these variations are 

 purely fortuitous and do not depend on age, sex, or locality. It is hard to find two terrapin alike." The 

 author does not believe the species was introduced into Buzzards Bay. An 8-inch terrapin, he thinks, 

 is 50 years old. 

 1899. Jordan, David Starr. — Manual of the Vertebrates, 8th edition, p. 209. 



This work contains a short description of Malaclemmys centrata Latreille. Under this name all 

 the diamond-back terrapin are included, but the work is of interest as being the first in which the 

 proper combination of generic and specific names occurs. 



GENERAL NATURAL HISTORY. 



Diamond-hack terrapins, so well known to connoisseurs and purveyors of sea 

 food, are distributed more or less continuously along the eastern coast of North and 

 Central America from Buzzards Bay. Massachusetts, to Yucatan." All the species are 

 lovers of salt or brackish water and tind their most congenial homes in low-lying 

 swamps and protected bays or inlets; but they also occur more or less abundantly in 

 nearly all the rivers that empty into the sea within the limits given, and they ascend 

 these rivers to points where the water is quite sweet. In the James River J/, centrata 

 is found considerably above Jamestown; in the York River it was formerly abundant 

 at West Point; in the Potomac individuals have been taken within 4 miles of 

 Washington. 



Of the habits of M. littoralis, M. pileata, and M. macrospilota, absolutely nothing- 

 is known except as observed in individuals transported to the pounds near Crisfield, 

 Maryland. Here they act much like 31. centrata, but go early into hibernation and 

 emerge late in the spring. 



The northern species, 31. centrata, is well known, and its habits have been care- 

 fully studied. Its period of hibernation begins soon after the advent of cold 

 weather, but for some weeks it emerges whenever there is a warm day. Eventually, 

 however, it buries itself completely at the bottom of some pool or stream and remains 

 until spring. Very soon after the winter sleep is over it seeks out others of its kind 

 and the process of reproduction begins. Conjugation usually takes place at night or 

 in the very early hours of morning, and always in the water, the diminutive male 

 being carried about on the back of the female. The eggs are laid during May or 

 June, for the most part. For a nest the female, with her hind legs, digs a hole in 

 some convenient bank, and at a depth of 5 or 6 inches deposits from 5 to 12 eggs. 

 She then crawls out, carefully covers up the nest, effaces every trace of her work, 

 and departs. The eggs hatch in about six weeks, if the weather is warm, but may 

 require twice as long if the season is a cold one. The young soon after hatching go 

 to the marsh and dig into the ground, where they spend the first winter and possibly 

 a part of the second summer. The growth is, for a turtle, fairly rapid, the average 

 increase in length being about 1 inch a year until 5 inches or thereabouts is 

 nached, when it becomes slower. Growth probably continues throughout the life 

 of the individual but in old age is so slow as to be almost imperceptible. Twentv- 

 five or thirty years is apparently the limit of life. 



o Their occurrence in Yucatan has been recorded by Gray (1855). It is quite possible that the range extends farther 

 t(i the southward, but Professor Agassiz's statement that it reaches some point on the coast of South America is not sup- 

 ported by any evidence. The genus MaXaclemmys does not appear in Cope's list of the reptiles of Mexico. 



