456 PEOFESSOR J. ANDERSON ON THE 



but are straight and directed forwards and downwards, the upper surface of the snout 

 being flat and not convex transversely as in Tupaia. The nasals are slightly dilated in 

 the middle, beyond which they contract posteriorly to a point, contracting also ante- 

 riorly, but again feebly dilating at their anterior extremities. They reach back to nearly 

 in a line with the anterior margin of the orbit ; and their posterior fourth is invested 

 externally by the frontals. The lateral concavity of the snout between the second pre- 

 molar and lateral incisor of Tupaia is absent in Hylomys, the sides of its snout being 

 almost straight. The maxillse reach a long way posterior to the nasals ; and in this the 

 skull differs both from Tupaia and Erinaceus. The prsemaxillae do not reach to the 

 frontal, but their inferior margin is on a line with the first premolar. In Tupaia the 

 skull from the parietal eminence slopes markedly downwards and backwards to the 

 lambdoidal crest, the two sides of which meet in a point, giving a triangular outline to 

 that portion of the skull ; and there is a semicircular interparietal. In Hylomys there 

 is only a slight depression between the vertex and the middle line of the lambdoidal 

 crest, which is almost on a level with the vertex, and not considerably below it as in 

 Tupaia. The lambdoidal crest is much truncated above, forming an obtuse angle with 

 its sides. This portion of the cranium, therefore, of Hylomys is much broader than in 

 Tupaia ; and the occipital region is slightly fuller, and, instead of sloping downwards 

 and forwards as in the latter genus, it is directed downwards and backwards, the 

 foramen ovale looking more backwards than downwards. In the character of the 

 hinder part of the cranium, Hylomys approaches more to Erinaceus^. The space 

 between the orbits is nearly flat, and is not so broad as in Tupaia ; neither is the orbit 

 enclosed by bone behind, nor the zygomatic arch perforated ; and in this it resembles 

 Erinaceus. The malar is a small spicule of bone applied to the outside of the perfect 

 zygomatic arch. It also approaches Erinaceus rather than Tupaia in its large infra- 

 orbital foramen and shorter canal, and in the prominent ridge at the anterior margin of 

 the orbit. The temporal fossa is large. The postorbital process, which, however, is 

 very minute, is more distinctly marked than in Erinaceus ; and immediately behind there 

 is a slight contraction of the skull, so that that portion of the skull is narrower than the 

 narrowest part between the orbits ; and in this respect also it resembles Erinaceus, and 

 differs from Tupaia. It is like the latter genus, however, in having the ridge from the 

 postorbital process, reaching backwards within a short way of the lambdoidal crest ; 

 but the sagittal ridge, which results from the union of the ridges of either side, is very 

 feebly developed, and before it joins the lambdoidal ridge it forms a flat triangular 

 surface, with the apex directed forwards. In Erinaceus these postorbital ridges are far 

 removed from the lambdoidal, by nearly half the length of the cranium. In Hylomys 

 the skull attains its greatest breadth at the posterior roots of the zygomata. The 

 palatal surface, unlike Tupaia and Erinaceus, has not any imperfections ; but a faintly 

 marked median ridge occurs as in Erinaceus. It is deeper than in Tupaia, and of more 

 ' I regret that there is no skull of Crymnura in this Museum with which to compare Hylomys. 



