ADDITIONAL SIWALIK PERISSODACTYLA AND PROBOSCIDIA. 15 
by Mr. F. Fedcleii from the Siwaliks of Perim Island. The crowns of the molars 
m. 1. a. pm. 4. J woro SO encrusted witli matrix that it 
specimen has^ accordingly 
structure of the teeth shows that they 
undoubtedly belong to a Hippotherium ; 
f d 6» C» 
T'ig 4. lUppotherium sp. nov.). Polished seotion and froiii the two first teeth being 
of three right upper cheek-teeth, in a fragment of the larger than the third, aild leSS fully 
maxilla ; from the Siwaliks of Perim Island, Gulf of , . 
Camhay: Indian Museum (No. C. 273). pi’Otruded, it IS eVldeilt that the 
former are the two last premolars, and the latter the first true molar. 
In the following table the dimensions of these three teeth are compared with 
those of the corresponding teeth of B. theohaldi figured in the second volume,^ vis . : — 
H. theohaldi. Specimen. 
Length of three teeth . 3‘3 3 ‘03 
,, ,, pm. 3 1-24 1-06 
Width „ 1-12 1-0 
Length ,, ,, 4 1’13 1*05 
Width „ „ „ 1-15 1-01 
Length ,, m. 1 . . . . . . . . . I'O 0'94 
Width „ 1-05 0-95 
The united length of the corresponding teeth of the Perim skull of B. antilopinum 
described above is 2 '23 inches ; and the present specimen is, therefore, nearer in 
point of size to H. theohaldi. Compared witli the slightly worn teeth of that species 
represented in vol. II., pi. XI., fig. 3, the present teeth differ by the section of the 
anterior pillar (e) being sub-circular, instead of markedly ellipsoidal, this character 
being most marked in the premolars : but agree in having the jiosterior pillar (/) 
connected with the adjacent inner crescent {d') hj a constricted neck : the shajie of 
this pillar differs, however, considerably, being elongated in B. theohaldi and rounded 
in the present specimen. In more worn teeth of B. theohaldi^ this pillar becomes 
almost completely merged with the first inner crescent (c) ; which would ajDparently 
never be the case with the present teeth. 
In B. antilopinum^ (as in B. gracile) the posterior pillar of the upper cheek-teeth 
is always well developed, and never shows a constricted junction with the adjacent 
crescent, except in a very early stage of wear : the anterior pillar has much the same 
shape and position as in the specimen under consideration. In none of the known 
examples of II. antilopinum^ does the length of pm. 3 exceed its width by so much as 
in the present specimen. Finally, the teeth of the latter are considerably larger than 
those of II. antilopinum. In the detached tooth represented in plate III., fig. 4, of 
this volume, which exhibits all the characters of H. antilopinum., the line of section 
is taken at precisely the same level as in the specimen under consideration ; and as 
1 Vol. II., pi. XIII., fig. 1. 
2 Vol. II., pi. XI., fig. 1 : ‘ F.A.S.,’ pi. LXXXII., figs. 13, 16, 18 : and pi. III., fig. 3, of the present volume. 
3 See table on page 12. 
