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The Megascoleeidae are supposed to have arisen from the same root 

 as the Moniligastridae but at a later period, and dates back at least to 

 the Triassie. This is the largest of the earthworm families and con- 

 tains more than half the known species. The family is widely distributed, 

 chiefly in tropical regions and the southern hemisphere. But one genus. 

 Diplocardia, is represented in our fauna. According to Michaelsen. this 

 genus probably appeared in Mexico or Central America during the Juras- 

 sic. Derivatives from this genus have spread into Africa, but the genus it- 

 self spread northward and is known from Mexico. Lower California, Texas, 

 Florida, Nebraska and Illinois. 



The Glossoscoleeidse seem to have developed as early as the Jurassic 

 in the northern continental area. The genus Sparganophilus of this fam- 

 ily is found in Mexico and various parts of the United States. Related 

 forms are known from Central and South America, where many species 

 are recognized. 



The Lumbricidse is recognized as the most recent family of the group 

 and is derived from the Glossoscolecidre, probably in southwest Asia. The 

 family is thought to have invaded Europe in the Eocene and North 

 America in the Oligocene. But few endemic species are known from the 

 United States. 



In the glaciated regions of the world, it is probable that the endemic 

 species have been destroyed during the Ice Age. These regions have been 

 repopulated by species which have migrated from the south and the earth- 

 worm fauna in such places is largely composed of forms carried in by 

 man. In the southern part of Europe are found many endemic species 

 while northern Europe is occupied almost wholly by forms also found 

 further south. The line separating the northern territory with peregrine 

 forms from the southern territory with endemic forms, corresponds very 

 closely to the line of the most southern extension of the glacial ice sheet. 

 It would be interesting to know if a similar condition exists in America. 



Last year, under the direction of Professor Frank Smith of the Uni- 

 verstiy of Illinois, I began a study of the earthworms of Illinois and 

 Indiana. I received, last. fall, some material from Mr. C. E. Allen, of 

 Wabash College, and scum' from my brother at Kewanna. During the 

 past summer I made some collections in several counties of the State but 

 was unable to make as extensive collections as are desirable. The ma- 

 terials I have contain some forms that may have to be described as new 

 species and I believe that careful collecting in the State will disclose 



