RHINOCEROS LEPTORHINUS. 381 



Etruscus. But the matrix is exactly like the Sansino of the Val d'Arno. 

 It is from the railway cutting near Dasino. 



There are also two upper premolars showing the bourrelet very strong, 

 but the crown still covered with matrix, of the same species and from 

 the same locality, with a yellowish ferruginous matrix. 



IX. — Description of the Cortesi Ehinoceros Cranium. 1 



Natural History Museum, Milan, April 24, 1861. 



The cranium, upon the Avhole, is in a very remarkable state of pre- 

 servation, and is now very much in the condition as described by 

 Cortesi in the ' Saggi Geologici.' It is entire, from the tips of the 

 nasal bones to the occiput; the left side of the occipital crest being 

 the part chiefly damaged. The skull, like Jourdan's Lyons Museum 

 Cranium (PI. XXXI. fig. 3), had undergone lateral pressure, so as to have 

 been slightly crushed. This is well shown on the basal aspect ; when 

 an axial line is drawn along the base of the sphenoid through the 

 palate, the palatal portion is seen to be deflected towards the right side ; 

 and the spheno-palatine bones are crushed. The whole of the right 

 zygomatic arch is present, but partly crushed in irpon the zygomatic 

 fossa. The crush has acted upon the palate, so as to elevate consider- 

 ably the series of molars upon the left side, above the plane of those of 

 the right ; the former being pressed a little outwards, the latter inwards, 

 upon the plane of the palate. The left zygomatic arch is partly wanting, 

 but the basal portions at either end are present, and the posterior stump 

 shows that a portion at least has been lost by a comparatively recent 

 fracture (since found). The mastoid process on the left side is broken 

 off, while the greater portion of the styliform process behind it is 

 present; vice versa, on the right side the greater portion of the mastoid 

 process is present, while the styliform is broken off. The two (occi- 

 pital) condyles are present, and nearly undisturbed, although somewhat 

 damaged ; the occipital part of the cranium has fortunately escaped 

 pressure; the lateral margins and crest on the left side are nearly 

 entire ; the upper third of the right side is broken off. The right occi- 

 pital condyle is traversed by two fissures; the left has lost a portion 

 towards the occipital plane. On making a further search among the 

 fragments in the case, I found the missing portion of the left mastoid, 

 which is now seen perfectly entire, and probably a further search 

 would lead to the discovery of some portion of the missing part of the 

 left zygomatic arch. I found the specimen taken off its stand, and laid 

 upon a pad of straw with the palatine surface uppermost, preparatory 

 to being drawn. Seen in this aspect, it bears a very close and remark- 

 able general resemblance to Jourdan's Lyons skull (PI. XXXI. fio-. 3 

 p. 36 ( J), which is also somewhat crushed, but in the reverse direction 

 {i.e. according to the lithograph), viz. from right to left (Cortesi's skull 

 being from left to right). The occipital condyles in the Lyons cranium 

 are obliquely displaced, while in Cortesi's skull they are in their natural 

 position. The bony part of the cranium is a good deal cracked and 

 shivered, so as to break off into minute pieces when the matrix is 

 detached ; but it is highly injected with ferruginous infiltration, and 

 completely mineralized. The matrix consists of a greyish yellow com- 

 pact clay (mania azzurra), which is hard and mottled with ferruginous 



1 Dr. Falconer was unfortunately not pormitted to take any drawings or casts 

 of this cranium. — [Ed.] 



