Some Observations upon the Development of the 

 Teeth of Physeter macrocephalus. 



By 

 Frank E. Beddard, D.Sc, M.A., F.R.S. 



With 13 Text-figures. 



On the following pages I describe the nature of the tooth 

 rudimerits in the very young embryo of Physeter macro- 

 cephalus, whose general external characters I have already 

 commented upon and figured (Beddard, 1). Since the material 

 upon which I have worked is, so far as I am aware, a unique 

 specimen only 4| inches long, I am particularly grateful to 

 the Curator of the Durban Museum (Mr. E. C. Chubb) for 

 placing it in my hands and to the authorities of the Museum of 

 the Royal College of Surgeons of England for allowing their 

 highly skilled assistant, Mr. Steward, to prepare a series of 

 sections for study. 



General Characters op Teeth in Foetal Sperm 

 Whale. 



Although the teeth of the adult sperm whale, of both lower 

 and upper jaws, are well known (Ritchie and Edwards, 5), 

 the development of the teeth in this cetacean is described in 

 only one memoir (Pouchet and Beauregard, 4), so far as I am 

 aware. This memoir contains a description of the teeth in 

 an embryo of 30 cm. ; those of both jaws are described and 

 figured. This embryo, it will be noted, is about twice the size 

 of that dealt with in the present communication. There is not, 

 however, as it would appear, a great deal of difference in the 

 condition of development of the teeth ; hence I have not 

 very much to add to the description of Messrs. Pouchet and 

 Beauregard. Apart, however, from such new facts as I am 



NO. 205 B 



