508 PROCEEDINGS OF SCIENTIFIC SOCIETIES. 
described. He thought that the element in Ichthyosaurus, called by 
eer the squamosal, was really the quadratojuga 
ext pointed out the various origins of the eulinmetiss a bone pecu- 
liar dí esie , and designed to support the roof of the cranium. In 
Ichthyosaurus and Dicynodon it originated from the squamosals, in tor- 
toises from the parietal, in crocodiles from the alisphenoid, and in lacer- 
tilia the origin could not be discov ered. 
He spoke of the proposition of Huxley, that some of the earlier types 
of reptilia in geologic time were not more generalized than those now 
existing. He took exception to goes and stated L the Dicynodon, 
( 
Thus he showed it had five characters of eheu xia, three of Tes- 
tudinata, two of Rhynchocephalia, three of Dinosauria, one of Lacertilia, 
and one of Crocodila. 
The system of Reptilia : oposed was the following: 
(A). Attached quadra 
I. Parts of M. de dinei, ribs two 
eaded to c i A Ichthyopterygia. 
II. Se ism differentiated : 
1. Hes ad of rib sessile on centrum tubercle to 
Testudinata. 
2. “Copa sariko on PE ihri on 
neura Archosauria. 
3. sails stid biterdi — Wiking to acid 
ch. 
a Synaptosauria. 
(B) Qu dinte, iia ioti lé. 
1. Ribs double headed; a quadratojugal. . -> Ornithosauria. 
ibs single headed; no quadratojugal. 
(2). No cisci a columella; opisthotic, all at- 
attached ; Lacertilia. 
(b). Alis snot no abot; ipiéibollt fixed, 
styloid; paddle Pythonomorpha. 
(c). alisphenoid; no aii opisthotie free 
mobile Ophidia. 
R J. B. ‘Peay rea d & paper on “The gopročćá Elevation and De- 
pression of the Continent during the Glacial Period.” Many geologists 
ane of the ages. Intense cold being thus occasioned by cosmical influ- 
s, the formation of an ice sheet of vast extent would naturally follow, 
pid if there were abundant moisture. The fact of intense igneou us 
activity, near the close of the Tertiary Period, suggests the occurrence 
of immense evaporation, and thus a source of aqueous supply. An ice- 
