Sellards — New Tortoise and a Supplementary Note. 235 



Art. XXV. — A New Tortoise and a Supplementary Note on 

 the Gavial, Tomisioma americana ; by E. PI. Sellards. 



In connection with a paper on pebble phosphates the writer, 

 in 1915, mentioned and illustrated a large land tortoise from 

 the Tertiary of Florida.* Additional specimens of this tortoise 

 have now been obtained indicating that it is a characteristic 

 and not uncommon fossil of the Florida land pebble phosphate 

 deposits. The species apparently is new and may be known as 

 Testudo hayi in recognition of the studies of Testudinata by 

 Dr. O. P. Hay. The type specimen of this species, which 

 includes a part of the carapace and plastron of a single in- 

 dividual, was contributed by the Phosphate Mining Company, 

 Nichols, Florida. A second specimen including a considerable 

 part of the carapace has been obtained from the Amalgamated 

 Phosphate Company, Brewster, Florida. Both specimens are 

 from the Bone Valley formation which is either of late 

 Miocene or of early Pliocene age. The origin of this forma- 

 tion has been discussed and a number of the vertebrate fossils 

 illustrated in the paper to which reference has been made. 



Testudo hayi, sp. nov. — This species includes large tortoises 

 which reach a size of approximately four feet in width by five 

 feet in length. The height of the carapace is estimated at 

 twenty-seven inches. Of the neurals the second is octagonal 

 or nearly so. The remaining neurals four to eight are hexag- 

 onal. The proximal end of the second costal is slightly 

 reduced in width and comes in contact with the second neural 

 only, while the third costal touches the second, third and fourth 

 neurals. The first or penultimate supra-pygal is large and 

 rests upon the eleventh marginals and the pygal. The second 

 or ultimate supra-pygal, on the contrary, is much reduced. 

 The length of the xiphiplastron from the bottom of the 

 xiphiplastral notch to the outer margin at the suture with the 

 hypoplastron is 300 ,nm . 



Under the name Testudo crassiscutata, Leidy in 1889 

 described a tortoise obtained on Peace Creek, Florida. The 

 type of Leidy's species includes portions of the anterior and 

 posterior lobes of the plastron, a femur and a tibia and frag- 

 ments of the carapace. By comparing the posterior part of 

 the plastron it is seen that the median notch of T. hayi is 

 deeper and more acute than is that of T. crassiscutata. The 

 exterior wall of the hypoplastron of T. hayi is vertical while 

 in T. crassiscutata the exterior wall of this bone slopes in- 

 ward. Although representing a larger individual the carapace 

 of T. hayi is thinner than that referred to T. crassiscutata. 

 *Fla. Geol. Surv., Seventh Annual Eeport, pp. 70, 75, figs. 7 and 9, 1915. 



Am. Jour. Sci. — Fourth Series, Vol. XLII, No. 249. — September, 1916. 

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