QUATEENAET FAUNA OF GIBRALTAE. 



103 



numerous fossil tibiae in the British Museum, and especially with one from the Thames 

 valley (No. 21884), termed R. leptorhinus, Owen. With this the Gibraltar bone 

 agrees very closely in size, form, proportions, section of shaft, and contours of articular 

 surfaces, whilst in all these respects it differs greatly from both Rhinoceros etruscus 

 and R. tichorhinus. The tibia of the former, a Val-d'Arno specimen (No. 28805), 

 while quite as long, is much slenderer in the shaft, with smaller articular surfaces ; 

 whilst in R. tichorhinus the tibia is thicker, shorter, and more massive in all its pro- 

 portions. 



The principal dimensions of the Gibraltar and Thames-valley specimens, together 

 with those of the Val-d'Arno tibia are as under : — 



Dimensions of Tibia in Rhinoceros. 



Gibraltar specimen 



Eford. Brady's collection 



Ditto ditto 



No. 21884, B.M 



R. etruscus, Yal d'Arno. No. 28805 . 



R. tichorhinus (Wirksworth) 



R. incisivus (Santan) 



R, unicornis 



c 



15-0 

 14-6 

 15-5 

 14-5 

 14-1 

 15-9 

 15-1 

 14'5 



5-1 X 4-9 

 5-2 X 4-9 

 x5-l 

 5-1 X 4-8 

 4-3 X 3-8 



4'6 X 4-4 

 5-5 X 5-5 



3-0 X 3-8 

 3-0 X 3-7 

 x3-7 

 2-7 X 3-9 

 2-4 X 3-4 



2-5 X 3-7 

 3-3 X 4-3 



•70 



6-2 



6-2 

 7-5 



.9 



•a 



•466 

 •472 



•439 



•410 

 •517 



From these figures will be seen the close correspondence, except perhaps in length, 

 between the three Thames-valley specimens and that from Gibraltar, and the distinc- 

 tion between them and the Etruscan form. 



5. Astragalus. 



Of this important bone, the collection contains two specimens in excellent preserva- 

 tion ; one, in fact, is quite perfect (PI. XV. fig. 3), and the other very nearly so. They 

 are both of the right side, and, as regards mineral condition and in all other respects, 

 precisely alike.^ The more perfect one was found cemented into the same mass of 

 breccia as the distal epiphysis of the tibia above described, into which, when cleaned, 

 it fits exactly. ■ There can be no doubt, therefore, that it belongs to the same 

 individual. 



The second astragalus was found in a different situation, viz. at 21 feet in the black 

 earth of the Genista cave, or at the same level very nearly as a metatarsal bone to be 

 presently described. But as all the rhinocerine bones are in the same state of mine- 

 ralization, they all doubtless belong to the same period. 



The principal dimensions of these astragali are given in the subjoined Table, together 

 with those of the same bone in some other extinct and recent species : — 



p2 



