108 DEUXIÈME ASSEMBLÉE GÉNÉRALE 
appearance of the Rhinocerotidæ and the appearance of South American 
Mammals. 
The zoogeographical changes are well known to enter a new relation 
by the invasion of the South American Edentata, namely, Glyptodon, 
Megalonyx, Mylodon. Among these a new Glyptodont. Glyptotherium 
LAW OF LOCAL ADAPTIVE RADIATION. 
Conremporarr Evorurion or Four Parcs 07 Tiraworneres , Lower Ouicocene , North America 






BRACHYCEPHALIC DOLICHOCEPHALIC BRACHYCEPHALIC MESATICEPHALIC 
Divergent MESOPODAL DoLICHOPODAL MESoPooAi 
Characlers SHORT HORNS SHORT HORNS, LONG WARROW HORNS LONG BROAD HORWS 
INCISOR TEETA NO INCISOR TEETA NO INCISOR TEETH INCISOR TEETA 
MEGACEROPS TITANOTHERIUM SYMBORODON BRONTOTHERIUM 
M. robustus | Serr B. platyceras 
Upper FF - ace B ramosum 
Beds ANGLE Al 
M. ti Oops Crassi- 
bicornufus Dr SANS 
; ‘ B_haîcher 
Midéle S copei : 
Beds B.tichoceras 
B.h perenes ve 
Lower RER 
Beds B. led yu 
Drrect Collateral | Direct Collateral | Collatral Direct Collalera! 
Tofal ihick- | Üne Unes line Unes lines line lines 
mess, 180 ft KE 
= 60 7m Ÿ LONG HORNED TITANOTHERES 
SHORT HORNED TITANOTHERES 
Fic. 7 
The law of local adaptive radiation illustrated in the four phula of Oligocene Titanotheres, 
one or more of which gave off collateral branches. 
Three of these phyla have now been shown to have a separate origin in the Middle Eocene. 
texanum has recently become known (OsBorx') from à nearly complete 
carapace and partial skeleton, which exhibits primitive affinities with the 
Eocene types of Patagonia. Among the Proboscidea the Stegodont stage 
appears in the so-called Mastodon murificus of Len, indicating a late 
Pliocene age for the Blanco formation. In the marine Miocene of Japan 
(wasaki and Yoshiwara?) the remarkable discovery has been made of an 
? Glyptotherium texanum. Bull. Amer. Mus. Nat. Hist., xix, 1903, pp. 491-494. 
? Notes on a New Fossil Mammal. Jour. Coll. of Sci. Imp. Univ. Tokyo, Vol. xvi, 
Art. 5, 1902. 
