942 ox TOOTH-GERMS IN A AVALLABY. 



upon mammalian dentitions, and which has in part been vised for 

 the purposes of this investigation. — H. W. M. T. 



Literature. 



1. Deppendorf, T. — " Zxu^ Entwickelungsgeschichte des Zahn- 



systems der Marsupialier." Semon's Zoolog. Forschungs- 

 reisen in Australien und dem malayischen Archipel," Bd. iii. 

 1897-1910, pp. 243-402. 



2. OsBORN, H. F. — " On the Structure and Classification of the 



INIesozoic Mammalia." Journ. Acad. Nat. Sci. Philadelphia, 

 vol. ix. p. 186. 



3. Rose, 0. — " Ueber die Zahnentwickelung vom Chameleon." 

 Anat. Anzeiger, Bd. viii. 1893, pp. 566-577. 



4. Semon, R. — "Die aussere Entwickelung des Geratodus forsteri." 



Zoolog. Forschungsreisen in Australien und dem malayischen 

 Archipel, Bd. i. 1893. 



5. Thomas, Oldfield. — "On the homologies and succession of 



the Teeth in the Dasyuridse, etc." Phil. Trans. Lond., 

 vol. 178,. 1888, pp. 443-462. 



6. Tims, H. W. Marett. — " Notes on the Dentition of the Dog." 



Anat. Anzeiger, Bd. xi. 1896, pp. 537-546. 



7. "The evolution of the Teeth in the Mammalia." Journ. 



Anat. & Phys. vol. xxxvii. 1903, pp. 132-149. 



8. " On the succession and homologies of the Molar and 



Premolar Teeth in the Mammalia." Jour. Anat. & Phys. 

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9. Tomes, C. S.— " Dental Anatomy." London, 1898. 



10. WiLSOX, J. T., & Hill, J. P. — •" Observations upon the 

 development and succession of the Teeth in Perameles, 

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12. Woodavard, M. F. — " On the development of the Teeth in the 



Macropodida;." Proc. Zool. Soc. Lond. 1893, pp. 450-471. 



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EXPLANATION OF PLATE XLVIL 



Fig. 1. Showing the deeply situated })ulbous rudiment of pra^ with the veiy long 

 neck of the enamel organ reaching to the surface of the oi-aI epithelium. 



Fig. 2. The enamel organ of pm-* with the labial downgrowth of the dental lamina 

 near to the free extremity of which is an enlargement, a '" concentric epi- 

 thelial body " {c.e.h.). 



Fig. 3. A " concentric epithelial body " more highly magnified. 



Fig. 4. Showing the sub-division of the enamel organ into two parts — ?a fusion of 



two distinct enamel organs. 

 .Fig, 5. Showing the presence of blood-vessels within the stellate reticulum of an 

 enamel organ. 



