CHELONE. 105 



The collection of the Academy of Natural Sciences contains a series of three 

 marginal plates, with the half of a fourth, from the Green-sand of MuUica Hill, 

 Gloucester County, New Jersey, presented by Mr. J. Colson and Dr. Wm. B. 

 Atkinson, which I suspect to belong- to a yoimger individual of the same species as 

 the preceding. 



The series, represented in Fig. 5, Plate XIX, without having the means to 

 determine their proper position, I nevertheless suspect to belong to the posterior 

 portion of the left side of the carapace. 



The plates rapidly increase in breadth passing backward. The inner border of 

 the series forms a continuous groove, with a deep costal pit in each plate. The 

 upper surface of the anterior plates slants evenly outward, but becomes slightly 

 concave in the posterior plates. The under surface corresponds with the upper. 

 The outer border is thin and acute, and at the junction of the plates appears to 

 have been somewhat crenate. The outer border of the third plate of the series as 

 it approaches the succeeding plate is notched half the width of the plate (e). The 

 posterior border of the last plate of the series articulated with the succeeding one 

 only at its outer half (/) ; the inner half (g) of this border being obtusely rounded, 

 and it extends close upon the costal pit of the inner border. The surfaces of the 

 plates are smooth or marked only by vascular grooves, and each is crossed by a 

 furrow (i) defining the boundary of the scutes. 



The breadth of the first of the plates is one inch and a half; its thickness inter- 

 nally ten lines. The length of the next plate is two inches eight lines ; its breadth 

 at middle one inch seven lines ; its thickness nine lines. The length of the suc- 

 ceeding plate is two inches seven lines; its breadth two inches and a quarter; its 

 thickness seven lines. The length of the last plate is two inches seven lines ; its 

 breadth two inches two lines ; and its thickness half an inch. 



Chelone ornata. 



Chelone ornata, Leidy, Proo. Acad. Nat. Sci., Pliila., 1856, VIII, 303. 



The museum of the Academy of Natural Sciences contains a specimen consisting 

 of conjoined portions of two marginal plates of a Turtle, obtained by Mr. L. T. 

 Germain, from the Green-sand of Burlington County, New Jersey. The specimen 

 is represented in Fig. 10, Plate XVIII, and though very imperfect is, nevertheless, 

 characteristic on account of its markings. The plates measure about an inch and 

 a half in breadth, and in transverse section are wedge-formed. Their iimer border 

 is eight lines high, and is grooved ; the outer border is acute. Both upper and 

 under surfaces slope evenly to the edges, and both are coarsely but beautifully 

 tuberculated. In the perfect condition of the plates the tubercles appear to have 

 had some tendency to a radiated arrangement. The fossil is supposed to indicate 

 a species of Chelone, though future discoveries may determine it to belong to 

 another genus. 



14 April, 1865. 



