1902.] ON EXTRA MOLAR TEETH IN A LEMUR FULVUS. 61 



4. Note on the Presence of an extra Pair of Molar Teeth 

 in a Lemur fulvus. By G. Elliot Smith, M.D., 

 Professor of Anatomy, Egyjitian Government Medical 

 School, Cairo \ 



[Received April 3, 1902.] 

 (Text-figure 1.) 



Among a number of Lemurs which Captain Stanley Flower, 

 Du-ector of the Ghizeh Zoological Gardens, has kindly placed at 

 my disposal during the past year was a male Lemur Julvus with 

 four molar teeth in each half of the mandible (text-fig. 1). 



Dr. Forsyth Major, whom I consulted on this matter as our 

 greatest authority on Prosimian anatomy, deems this anomalous 

 condition worthy of being placed on record. 



The individual in which these additional teeth were found had 

 attained to the full adult proportions, but the cranial sutures 

 were still distinct. 



The teeth of the maxilla were normal in number, size, and shape. 

 All of the teeth usually found in the mandible of this species 

 of Lemur were also present in this specimen, and none of them 

 deviated in any respect from the condition normal to the species. 

 But there was present behind each third lower molar a tooth of 



Text-fig. 1. 



Left lateral aspect of the anomalous mandible of Lemur fulvus. ^ , nat. size. 



approximately the same form and four-fifths of its dimensions. 

 The only difierence in shape, which a careful comparison of the 

 third and fourth molars revealed, was due to the diminutive 

 proportions of the postero- external cusp of the latter. 



According to Tomes, some of the extinct species of Lemurs 

 have "the full mammalian number of four premolars, and so 

 were . . . less specialized than their recent descendants." ^ 



The anomalous case now described is, in a sense, compensatory 

 to the last-quoted, for it possesses four molars and only three 

 premolars. 



The tendency to the persistence of the primitive number of 

 four molars is" seen in its most pronounced form in the Order 



1 Communicated by Prof. G. B. Howes, F.R.S., F.Z.S. 



2 C. S. Tomes, 'Dental Anatomy,' 5th ed., 1898, p. 501. 



