626 DR. o. I. li'ORSYTH MAJOR ON A [Dec. 17, 



postorbital processes is elongate and contracted, the rostrum short 

 and broad, the orbits elevated, the infraorbital foramen large. 



The ventral region of the skull was at first concealed by strongly 

 adhering stalagmitic matrix ; when this was disengaged, remarkable 

 divergences from the Lutra became apparent. The posterior 

 portion of the region still recalls Lutra by its lateral expansion, 

 flattened hullce ossece, and broad basioccipital and basisphenoid. 

 But the broad palatal region between the teeth, and the very 

 elongate bony palate behind the tooth-series, are in striking 

 contrast with all known species of Lutra, and approach on the 

 other hand to some genera of the Mustelinae, viz. Putorius and 

 Galictis. 



The dentition is undoubtedly that of a member of the Muste- 

 lidse. There appears to be no trace of a fourth, anterior, premolar, 

 another agreement with the two last-named genera. The most 

 striking peculiarity of the upper dentition is in the shape of the 

 carnassial, the one on the left side being foi'tunately almost 

 completely preserved. 



In the Lutrinae the heel of the carnassial is a broad, approxi- 

 mately semicircular lobe, either embracing the whole of the blade, 

 or leaving free not more than the posterior third. In the Musteline 

 the heel is generally represented by a comparatively small cusp 

 near the antei'ior end of the tooth, from which it is well separated 

 by a constriction. The fossil tooth holds an intermediate position. 

 The heel is broad as compared with the majority of the Mustelinae 

 and shows throughout a raised margin encircling a cup-shaped 

 area ; starting aateriorly from the small antero-external cusp of 

 the blade, it embraces not more than about the anterior half of 

 the latter. 



The only recejit Mustelines presenting a similar carnassial are 

 those of the Galictis group {Galictis, Galera, Lyneochn), and more 

 than the other species, the Galictis vittata, in which the heel 

 extends less medially than in the larger species. The only 

 appreciable difference from the fossil is the slightly stronger 

 antero-external cusp, which makes the heel of the (ra^icifis carnassial 

 appear to be situated more backward. 



The molar of the fossil is only preserved on the right side ; it 

 is much worn and slightly damaged near the antero-internal corner. 

 Although this tooth, placed as it is at the end of the series in the 

 Mustelidse, varies much in this family, even from one species to 

 the other, it is noteworthy that the molar of the fossil again comes 

 nearest to the smaller species of Galictis. It is a narrow tooth, in 

 which tlie length of the external boi'der is equal to that of the 

 internal, and the anterior margin runs approximately parallel to 

 the posterior. 



From the description and comparisons it results that the 

 Sardinian fossil belongs to an amphibious member of the Mus- 

 telinsB, coming nearest among recent forms to the South- American 

 Galictis, It is abundantly entitled to constitute a separate genus, 

 and I have accordingly called it 



