12 AMERICAN MESOZOIC MAMMALIA 



Eucosmodon Matthew & Granger 1921 



Ectyfodus Matthew & Granger 1921 



Prionessus Matthew & Granger 1925 



Paronychodon Cope 1876^ 



Menisco'essus Cope 1 882* 



Difriodon Marsh 1889^ 



Ciniolodon Marsh 1889 



Cifnolomys Marsh 1889 



Essonodon Simpson 1927 



Djadochtatherium Simpson 1925 

 Family Taeniolabididae Granger & Simpson 1929 



Taeniolabis Cope 1882 



Catof salts Cope 1 882 

 Incertae sedis: 



Family Microcleptidae Simpson 1928 



Microcle-ptes Simpson 1928 



Thomasia Poche 1908 

 Inc. sed. : Hy-psi-prymnofsis Dawkins 1864 



The suggested relationships of the various larger groups are as follows : 



Ptilodontidae Taeniolabididae 



\ / 



X 



\ 

 Plagiaulacidae 



Tritylodontidae Microcleptidae / 



\ 



"\ 

 TRITYLODONTOIDEA PLAGIAULACOIDEA 



/ 



MULTITUBERCULATA 



T 



Only the families Plagiaulacidae and Ptilodontidae of the suborder Plagiau- 

 lacoidea occur in the American Mesozoic. 



* On the validity of these three genera, see below. 



