1887] ; Zoology. 89 
on the hill-top, subject them to a needless torture. If water is 
given them, they will quickly stick their heads into it, and then 
hold them upright as birds do when drinking. 
In autumn they do not always dig under the soil to pass the 
winter in this locality, but will hibernate in a hollow or any 
place where a thick mass of leaves has collected. I found one 
on the 8th of February, 1885, in such a location, with but few 
leaves for a covering.— William T. Davis. 
On the Morphogeny of the Carapace of the Testudinata.— 
Preliminary to a more extended paper on the group Athece of 
the Testudinata, allow me to give the following results, which 
seem to be of considerable interest: 
The Dermatochelyde (Sphagididz) are characterized by the 
development of independent superficial dermal bones. In Der- 
matochelys coriacea and the allied extinct forms we find a pave- 
ment of small osseous plates extending over the whole shield, 
jointed to each other by more or less fine sutures. The number 
of these plates is very much larger than that of the other Testu- 
dinata, which never have more than seven 
In all other Testudinata we find the carapace connected with 
the internal skeleton. That the carapace of the Dermatochelyde 
is homologous to the carapace, without internal skeleton, of the 
rest of the Testudinata, there is no doubt; that the carapace of 
the “Thecophora” (Dollo) has developed from the carapace of 
the “ Athecæ” is proved by a specimen of Eretmochelys imbricata. 
In this specimen I find small polygonal plates of the same shape 
as those of Dermatochelys suturally connected with the third, 
fourth, fifth, and sixth costal plates. 
A form between the Dermatochelyde and “Thecophora” 
(Dollo) is represented by the oldest known turtle Psephoderma 
alpinum Hi. v. Meyer, from the Triassic of the Bavarian moun- 
tains, preserved in Munich. In this highly-interesting specimen, 
never mentioned in monographs on the Testudinata, we have 
certainly not less than one hundred and ninety-three plates 
suturally united*—Dr. G. Baur, Yale College Museum, New 
Haven, Conn., October 6, 1886. 
* It is important to mention that Dermatochelys has the nuchal plate developed 
besides the mosaic-like carapace. According to Gervais, this plate is covered by 
