SKULL OF A PARIASAURIAN REPTILE. WA 7 
‘Pineal foramen far back to far forward. Occiput composed of a 
plate with small laterally placed post-temporal vacuities ; supra- 
occipital overlapped by the vertically placed interparietals and 
tabulares, which reach down to the opisthotics. Brain-case 
very high ; opening to inner ear placed very low down. Stapes 
in contact with quadrate. Quadrate small to very small, almost 
completely overlapped behind by the squamosal. Quadratojugal 
usually absent, but sometimes represented by a rudiment. Palate 
very variable, showing the gradual development of a mammalian 
type from an almost typical primitive reptilian palate. (It is 
completely known in very few types.) 
Septomaxillary always present on the face or in the nostril. 
Lower jaw with flat angular, with a deep notch overlaid by a 
reflected lamina, which becomes rudimentary in later forms. 
About 28 presacral vertebree, three or four sacrals. Inter- 
centra in the front part of the column. Ribs double-headed in 
front, single-headed behind. 
Scapula with or without an acromion. Two coracoidal 
elements, the anterior excluded from the glenoid cavity, clavicles 
and broad flat interclavicle always present, cleithrum present or 
absent. 
Humerus short and expanded to long and very slender, always 
twisted ; entepi- and ectepicondylar foramina always ? present. 
Carpus (only few types) with two centralia and five distalia. 
Five digits; formula 2, 3, 4, 5, 4, later reduced to 2, 3, 3, 3, 3. 
Pelvis without a pubo-ischiadic vacuity in early types, with one 
in later forms. 
Dromasauria. (Galecheirus, etc.) — 
Small arboreal reptiles with long slender limbs. 
Skull short, with one temporal vacuity bounded by the squamosal 
and postorbital and @jugal. Pineal foramen far back. Preparietal 
present (?). Occiput very badly known but apparently very 
similar to that of a Deinocephalian. Kar and _ brain-cavity 
unknown. Quadrate unknown. Quadratojugal probably absent. 
Palate unknown. Lower jaw with large dentary and apparently 
flat notched angular. 
Tail very long. 
Scapula without acromion, two large coracoidal elements. 
Clavicies and broad flat interclavicle. 
Humerus long, very slender, and twisted. 
Carpus with two centralia ; digital formula 2, 3, 3, 3, 3. 
Pelvis with small upright ilium and large plate-like pubis and 
ischium. 
Femur very long and slender. Tarsus with two proximal and 
four distal tarsals and one centrale. Digital formula 2, 3, 3, 3, 3. 
Proc. Zoou, Soc.—1914, No. XII. 12 
