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Scientific Intelligence. 



from trie oolitic slate of Stonesfield, Oxfordshire, for "which the name of 

 Stereognathus ooliticus had been proposed ; and after a minute descrip- 

 tion of the characters of the bone and teeth, he entered upon the ques- 

 tion of its probable affinities. These could only be judged of by the pe- 

 culiarities of certain molar teeth of the lower jaw of the unique fossil. 

 Those teeth presented the singular complexity of six cusps or cones upon 

 the grinding surface, in three longitudinal pairs, the crown of the tooth 

 being quadrate, broadest transversely, but very short or low. The jaw- 

 bone presents a corresponding shallowness and thickness. The cusps are 

 sub-compressed : the outermost and innermost of the three hinder ones 

 are oblique, and converge towards the middle of the crown, being over- 

 lapped by the outermost and innermost of the three front cones. The three 

 molar teeth occupy the extent of 4-^ lines, or 1 centimeter ; each tooth 

 being 3 millimeters in fore and aft extent, and nearly 4 millimeters in 

 transverse extent. After a comparison of these molars with the multi- 

 cuspic teeth of the rat, the hedgehog, the shrews and Galeopitheci, the 

 author showed that the proportions, numbers and arrangement of the 

 cusps in those Insectivora forbad a reference of the Stereognathus, on den- 

 tal grounds, to that order. The same negative result followed a compari- 

 son of the fossil with the sex-cuspid teeth of the young Manatee. The 

 author finally proceeded to point out closer resemblances to the sex-cuspid 

 teeth of the mammals of the eocene, Hyracothere, Microthere and Hy- 

 opotamus ; but in these the resemblance was presented only by the teeth of 

 the upper jaw. The lower molar teeth of the Chceropotamus, to which the 

 author deemed those of the Hyracotherium would most closely approxi- 

 mate when discovered, showed a rudiment of the intermediate cones be- 

 tween the normal pairs of cones. The proportional size and regularity 

 of the cones of the grinding teeth of the Stereognathus, give quite a 

 different character of the crown from that of the multicuspid molars of 

 the Insectivora, and cause the sex-cuspid crown of the oolitic mammal to 

 resemble the pen te- cuspid and quadri-cuspid molars of the before-cited ex- 

 tinct Artiodactyle genera. Prof. Owen concluded, therefore, that the 

 Stereognathus was most probably a diminutive form of non-ruminant Ar- 

 tiodactyle, of omniverous habits. 



7. On the Dichodon cuspidatus, from the Upper Eocene of the Isle 

 of Wight and Hordwell, Hards ; by Prof. Owen, (Proc. Brit. Assoc., 

 Aug. 1856 ; Ath., No. 1503.) — Prof. Owen communicated the results of 

 examinations of additional specimens of jaws and teeth of the Dichodon 

 cuspidatus, which he had received since his original Memoirs on that ex- 

 tinct animal in the Quarterly Journal of the Geological Society, vol. iv., 

 (June, 1847). The first specimen described supplied the characters of the 

 last true molar tooth of the lower jaw, which had not been previously 

 known. This tooth has six lobes, the additional posterior pair being less 

 than the normal ones, and more simple. The inner surface of the inner 

 lobe has an accessary cusp at the back part of its base, but not at the fore 

 part as in the other lobes. The length of the last lower molar was nine 

 lines, that of the first and second molars being each six lines. A speci- 

 men of the Dichodon cuspidatus from the Hordwell Sands, in the British 

 Museum, supplied the characters of the permanent incisors, canine, and 

 three anterior premolars of the upper jaw : all these teeth closely corres- 



