Diversity in the Scutes of Chelonia. 75 



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EXPLANATION OF PLATES. 



Figs. 1-13, plates I-VI, photographs of shells of diamond-back terrapin. 



Figs. 14-54, plates VII-XI, sketches of plan of scutes of diamond-back ter- 

 rapin ; when only a portion of the carapace is shown, the drawing is from 

 a field-sketch; Fig. 51 omitted; Figs. 53 and 54 from terrapin of Texas (see 

 p. 31). 



Figs. 55-104, plates XI-XIV, drawings of plan of scutes of embryos and new- 

 born of the loggerhead sea-turtle. 



In the first eleven plates the figures in parentheses folloicing the number of 

 the illustration refer to the serial number of the specimen in tables 7-7; in the 

 succeeding plates (and in plate XI if preceded by the letter "T") the numbers 

 refer to the specimens of Thalassochelys of tables VI-JX, 



