1896.] • SkCllS of a iiiiMTJii AWi) OraNG, ■ 96? 



they were not uncommon in the genus Lemur, especially in young 

 individuals, although their existence had apparently nob been 

 recorded. The bones in the s])ecimen examined by me are tri- 

 angular in form and, as will be realized from the sketch (fig. 1), occupy 



Fig. 1. 



Skull of Lemur, from above. 



Fr. Frontals. x. Supernumerary bones. L. Lachrjmals. N. Nasals. 

 . M. Maxillae. 



a positiou corresponding with the prefrontals in a Lizard or Croco- 

 dile. The suture which marks their limits is very clearly defined. 

 It is interesting to note that corresponding bones have been 

 recognized in the genus Hippopotamus. In a memoir ' contributed 

 to tome xvi., 1894, of the ' Annales des Sciences Naturelles ' by 

 MM. Grandidier and Pilhol, for a reference to which I am indebted 

 to Sir W. riower and Dr. Forsyth Major, these bones are described 

 and figured both in the case of an extinct species, 11. lemerlei, 

 from Madagascar and of young individuals of existing Hippo- 

 potami from Senegal. On examination of our only specimen of 

 the skull of a Hippopotamus in the Museum of Queen's College, 

 Belfast, r find the same bones (regarded by MM. Grandidier aud 

 Filhol as representing prefrontals) distinctly indicated, though the 

 suture separating them posteriorly from the frontals is to a con- 

 siderable extent obliterated. 



In Sir W. Flower's admirable ' Introduction to the Osteology of 

 the Mammalia' (3rd edition), tlie following statement occurs 

 (p. 102) with respect to the squamosal in Moidseys : "The squamosal 

 in the higher forms is developed much as in Man, but in the lower 

 forms it is more reduced and takes a smaller share in the formation 

 of the side-wall of the cranium. It generally comes in contact at 



^ " Ossements d'Hippopotames." 



