DEVELOPMENT AND SUCCESSION OF TEETH IN PERAMELES. 439 
noted that the author refers the adult incisors of Macropods 
to the first dentition, accepting, as he does, the criterion 
which had seemed sufficient to Kiikenthal and Rose. He 
says, ‘‘If these various and often minute cord-like down- 
growths of the dental lamina (lingually to the enamel-germs 
of the adult incisors) are to be interpreted as representing 
rudiments of teeth, as seems probable from comparison with 
the known rudiments of the first or second dentition in other 
mammals, then we find that in the kangaroos the incisor 
teeth all belong to the first dentition, that the relations of the 
canines are uncertain,” &c. &c. Again, on account of the 
presence of a “distinct but small” lingual downgrowth by 
the side of the enamel-germ of the foremost upper vestigial 
tooth, Woodward referred that tooth to the first dentition 
equally with the germs of the adult teeth; and he extends the 
same determination to the other two, partly from their 
general analogy to the first, and partly on account of certain 
observations as to their relative position in reference to the 
dental lamina, and to the enamel-germs of the neighbouring 
adult teeth. 
Similar reasonings prevailed with him in regard to the 
lower incisors, and accordingly he is led to interpret the 
vestigial incisors simply as decadent members of the same 
series to which the adult teeth belong. 
Mr. Woodward’s paper constitutes the earliest publication 
in which were recorded observations upon the presence of 
undoubted embryonic vestigial teeth in Marsupials. Rdése’s 
paper, dealing with such structures in wombat, was not pub- 
lished till 4th August, 1893. 
On the same day there appeared in the ‘ Morphologisches 
Jahrbuch,’ Bd. xx, a paper (12) by Professor W. Leche, which 
bore the date January, 1893. This contribution was supple- 
mentary to his paper (13) in the preceding volume on the 
subject of mammalian tooth-development, and it contains an 
account of his researches into the development of the teeth of 
Myrmecobius, to which in his previous paper he has 
referred as still in progress, 
