636 The Leather Turtle. [ October, 
which was obtained by Prof. Paul Gervais, and the skeleton pre- 
served by him for the Museum d’Histoire Naturelle at Paris. 
The great age of the genus in Europe is also shown by the dis- 
covery of Sphargis pseudostracion Gervais, in the Miocene, near 
Montpelier. Protostega gigas Cope, from the Cretaceous of Kan- 
sas is closely allied to Sphargis coriacea, though a much larger 
species, the length being 12.8 feet and the width from tip to tip 
of the anterior flippers, 11.3 feet. 
Two other species, P. neptunia and P. tuberosa, the former from 
the Cretaceous of New Jersey and the latter from the same forma- 
tion in Mississippi, have also been described by Prof. Cope, which 
seems to prove that the genus Protostega was quite as preva- 
lent in Cretaceous seas as is Sphargis in those of the present. 
Unfortunately the specimen captured in Delaware bay and 
brought to Philadelphia, lived but a short time afterward; its 
death having been hastened by an injury received from a boat 
hook or other weapon during the struggle to capture it. 
The chance of seeing such a huge denizen of the ocean was 
a rare one, however, and very many citizens, including some 
eminent naturalists, took advantage of it. As a precautionary 
measure, the animal was kept upon its back; nevertheless, the 
muscular power displayed by the creature when trying to regain 
its normal position was something remarkable. Especially was 
_ this the case just previous to dying, when, according to its owner's 
statement, the united efforts of four men were required to keep it 
in place. 
During a quiet interval the subjoined measurements were 
taken by the writer, kindly assisted by that careful naturalist, Mr. 
John A. Ryder: 
Feet, Inches. 
Entire length of animal 6 7 
Kengi ol earapaee 50. e605 os oo5 os go 
Greatest width of same Brot 
From tip to tip of anterior jae. By age 
Greatest width of anterior flippers I o 
From point of SRE to edge of carapace I 3 
Diameter of neck I o 
Elevation .. I 4 
Width of breast R 3 o 
Length of tail o $ 
As a subsequent measurement suggested no alteration of the 
figures given they may therefore be accepted as approximately 
