GEOLOGIC HISTORY OF THE LOCUST 293 



Asia and North America it must have been present during the 

 Tertiary in the intervening region, as I have already remarked. 

 This hnpHes its presence in not only the Arctic region but in 

 northwestern North America and very prol)ably in Europe. Its 

 former presence on the last continent has not been definitely 

 proven, however. Saporta, many years ago described leaflets 

 and pods from the basal Miocene of France as Gymnodadus 

 macrocarpa, but these are usually regarded as more properly 

 referable to some other leguminous genus. Squinabol named a 

 pod from the Oligocene of Italy Gymnodadus novalensis but this 

 too is of doubtful identity. An undoubted fossil form has been 

 found in North America. This is Gymnodadus casei and it 

 comes from the late Miocene of the ''panhandle" region of 

 Oklahoma. It was much like the modern Coffee-tree and is of 

 interest chiefly in showing that at that time the western range 

 of the genus was not as restricted as it is to-day. 



There are also fossil leaflets found in the late Miocene of cen- 

 tral France that appear to represent a European Gymnodadus. 



THE JUDAS-TREE (Cercis) 



Unhke the great majority of leguminous genera the different 

 species of Cercis have simple leaves. These are cordate-orbicu- 

 lar in form, glossy green, palmately 5 to 7 veined and arranged 

 in a two-ranked manner on the long shoots. The pods are small 

 and compressed, lustrously red purple in color, and fall in the 

 late autumn or early winter. There are five or six existing 

 species of Cercis although the majority of my readers will be 

 familiar with only the European Judas-tree or its very smiilar 

 American relative. In addition to these two well known orna- 

 mental trees there is a third species in Texas, another on the 

 Pacific coast of North America, and two or three more in south- 

 western, central, and eastern Asia. Thus Cercis is another 

 genus w^hose distribution suggests the same thoughts as did the 

 distribution of Gymnodadus. But in the case of the former 

 more links in the chain have remained until modern times and 

 its distribution to-day suggests what may have been and 

 probably was the distribution of Gymnodadus in Miocene times. 



