1883.] 



NATURAL SCIENCES OF PHILADELPHIA. 



83 



here proposed as do the opossums, but it differs from the latter 

 in having the anterior intermediate tubercle the larger, instead of 

 the posterior. Mystomys and Solenodon also confirm my deter- 

 mination of the homologies in Gentetes} 



In conclusion I give the following synoptic view of the consti- 

 tution of the superior molar teeth in various genera of the 

 Bunotheria. 



Cusps Present. 



1 This view was first advanced by the writer in the Annual Report U. S. 

 Geol. Survey Terrs., 1873 (74), p. 472. 



