48 MR. M. F. WOODWARD ON THE [Jan. 5, 



There can be very little doubt that the Duplicidentata, as concerns 

 their teeth, are the most primitive living Rodents ; and as the 

 deciduous front incisors have almost disappeared in them, we could 

 hardly expect to find them present in the more modified forms, 

 where the teeth are reduced in number. It is, however, highly 

 probable that we might find them in the Hare and possibly in 

 Lagomys, 



Krause (17), in describing the deciduous teeth of the Rabbit, 

 gives the formula i. j pm. -' which, as I have shown, is the correct 

 one ; but although he gives the correct formula, he cannot have 

 seen the small deciduous first incisors ; in fact, he says {op. cit. p. 1 99) 

 " the four large incisors persist from the beginning " ; so that he 

 counts the large cntting-incisors twice over, first in the deciduous 

 and afterwards in the permanent dentition, solely on the grounds 

 that they happen to be formed very early, when none but rnilk- 

 teeth are present in the jaw. 



The discovery of these teeth is entirely due to Huxley, but as he 

 only mentioned it in a passing footnote appended to a paper dealing 

 with much wider questions, and as he never figured them, I append 

 figures, in illustration of my more detailed account of them. 



In concluding, I should like to express my thanks to Mr. Oldfield 

 Thomas for his kind assistance in allowing me access to a fine series 

 of Hyrax skulls in the British Museum, and to Prof. Howes for his 

 valuable advice and suggestions during the progress of this work. 



V. List of References. 



1. Blainville. Osteographie, t. vi. p. 38. 



2. Brandt, J.F. "Ueber d. Gattung d. Klippschliefer (iry?-«.r)." 



Mem. Ac. Petersb. (7) xiv. 1869. 



3. CuviER, F. Dents d. Mammif. 1825. 



4. CuviER, G. Ann. d. Mus. Paris, t. iii. 1804, p. 177. 



5. . Recherohes s.l. oss. Fossil. 4th ed., t. iii. 1834, p. 253. 



6. Flower, W. H. "On the Homologies of the Teeth of the 



Mammalia." J. Anat. Phys. vol. iii. 1869, p. 262. 



7. . " On the Milk Dentition of Mammalia." Trans. Odoiit. 



Soc. 1871. 



8. . " On the Succession of the Teeth in the Marsupialia." 



Phil. Trans, vol. 157, 1867, p. 631. 



9. Flower, W. H., & Lydekker. " Mammalia." Lond., 



1891. 



10. George. " Monogr. Anat. d. Daman." Ann. Sci. Nat. (6) 



t. i. 1874, Art. 9, pp. 83-86. 



11. Gervais. Hist. Nat. d. Munimif. 1855. 



12. GiEBEL. Odontographie, ]>. 75, 1855. 



13. . Bronn's Thier-Reich, Bd. vi. Abth. v. p. 118, 1875. 



14. Gray, J. E. Cat. of Carniv. and Pachyderm. Mamniiilia 



Brit. Mus. 1869. 



