852 ROBERT COLLETT. 



to have been broken. From the pits it can be seen that they were 

 placed about 5 — 6 mm apart, and the covering of hair is thus very 

 thin. They are, however, comparatively evenly distributed; also on 

 the tail traces of hair are found, although they appear to have been 

 more scarce there. 



The skull. 



A B 



mm mm 



Length 265 452 



Breadth across zygomatic arches 160 245 



Greatest breadth of intermaxillaria (across the narial 



aperture) 85 140 



Length of zygomatic arch 136 235 



Length of Symphysis of intermaxillaria 107 238 



Least width of upper part of parietalia 60 65 



Greatest length of narial aperture 76 145 



Greatest breadth of narial aperture 49 80 



Length of lower jaw 182 332 



Least height of lower jaw (to front edge of m^) . , 52 91 



Length of tooth-series on Symphysis of the lower jaws 57 136 



In comparison with the skull of the mature female specimen, the 

 young one is distinguished by a proportionally shorter snout (shorter 

 Intermaxillaria and Symphysis of the lower jaws), and proportionally 

 broader parietals and frontals. Otherwise it differs in but a slightly 

 and unimportant degree from the mature specimen. 



These diöerences are chiefly the following: — Whilst the condyli 

 occipitales in the mature specimen are formed exclusively of the exoc- 

 cipitalia, the hinder part of the basioccipit ale in the young 

 one also participates in forming the condyli. 



The parietalia are comparatively broadinthe young; the upper, flat 

 part is even in its latter portion somewhat arched in the centre, and 

 the margins rounded off without a trace of crests. The absolute width 

 is in reality almost as great in the young as in the mature specimen 

 (which is about three times as large) — see table of measurements. — 



The transverse section of the parietalia, measured between the mar- 

 gins of the temporalia, is thus in the young one not to any great extent 

 less, than the length of the narial aperture, whilst the same transverse 

 section in the mature specimen does not extend to half the length of 

 the aperture. 



