PART ].] 
Li/dukker : Notiees of Siwalik Mam ma fit. 
99 
In this notice 1 shall content myself with pointing out the main distinctions of 
the teeth of the fossil specimen from those of H. leucura, which are indistinguish¬ 
able from those of H. cristata. The dimensions of the two first molars of E. 
leucura are compared below with those of the fossil teeth :— 
Fossil. 
Ivooeut, 
hi. 
Ill. 
Length of two first molars 
• 
. 0"75 
0-71 
„ of first molar 
. 0-39 
0-35 
Width of „ „ 
. 
. 0-33 
U-29 
Length of second ,, 
. 0-36 
0-3(> 
Width of „ „ 
. 0-31 
0-28 
From these dimensions it will be seen that in the fossil jaw the first molar is 
longer than the second, while precisely the revei'se of this occurs in the recent 
jaw; the first molar of the fossil is considerably larger than that of the receni 
jaw, while the second molars of the two are of the same length, but that of th<! 
fossil is wider. Since the smallest of the fossil teeth is as large as the largest of 
H. leucura, the matter of size \\dll distingush the fossil form from the two smaller 
Indian species, H. bengalensis and H. longicauda. 
Now, for the form of the teeth, in H. leucura the lateral enamel fold at the 
middle of the inner side runs only for a very short distance at right angles to the 
long axis of the tooth, and is connected for a long time with the fold at the 
antero-extemal angle of the crown, and is isolated after its severance ; in the fossil 
jaw this fold I’uns for some distance at right angles to the same axis, is never 
connected with the antero-extemal fold, and is not isolated at all in the specimen. 
Other differences occur in the form of the grinding surface, which require a figure 
for their explanation; as minor difference.s, the surface of atti'itionof the incisors 
in the fossil jaw is more concave, and the muscular ridges of the latter are much 
more strongly marked than in the living species. These differences sutticicntly 
distinguish the Indian fossil nystrix from the living species of the genus. 
The only fossils of the genus with which I am acquainted are certain frag¬ 
mentary sfiecimens from the Val d’Arno' of which the species is not deter¬ 
mined; H. refossa from the sub-volcanic alluvium of Puy deDome^; II. pri- 
migenia from the upper miocene of Attica®; and H. venusta from the pliocene 
of North America.^ 
I can say nothing with regard to the unnamed species ; if. refossn ha.s the ena¬ 
mel islands unusually numerous, and the external fold very slight, and therefore 
differs from our specimen: if. refossa is considered by M. Pomel to be an agonti.' 
In if. primigenia the large inner enamel fold of the lower molars agrees in the 
matter of length with the same fold in the fossil Indian species, but it seems to 
be sooner isolated ; the form of the minor folds is also different in the two, and 
* Cuvier: “Osseiuens Fossiles,” 4th Ed., V’ol. VIII, p. 128. 
® Gervais: ‘‘Zoologie et Paleontologie Fran^aises, ” pi. XLVIIl, fig. 11. 
® Gaudry: “ Animaux Fossiles de I’Attique,” pi. XVIII, fig. 2. 
‘Leidy: “Extinct Mammalia of Dakota and Nehrasca,” p. 343, pi. 2fi, figs. 23 & 24; the 
species is there named M. venustus, which I have ventured to alter to M. venusta, Mystrix being 
feminine. 
* Pictet; “Traite de Paleontologie,” Vol, I, page 255. 
