Natural History of District of Columbia — McAtee 71 



of alleghenian affinities, another way of saying that in this 

 region they are restricted to the Coastal Plain and Piedmont 

 Plateau respectively. Among hymenoptera, the following, 

 I am informed by Mr. H. L. Viereck, are confined to the 

 Coastal Plain : Perdita novi-angliae, P. halictoides, Andrena 

 miser abilis, Bombius Scutellaria, Pepsis clegans, Stictia 

 Carolina, and Bembix cinerea. Knowledge of the local dis- 

 tribution of these and other groups of insects is not so 

 detailed as in the case of the Orthoptera. If it were, sta- 

 tistics as to their relation to the fall line would no doubt be 

 fully as impressive. 



A similar distinction between the life of the Piedmont 

 Plateau and the Coastal Plain is not so clearly reflected in 

 the higher groups such as mammals and birds. Nor should 

 it be expected. Both of these orders are much better equipped 

 for migratory movements than either plants or insects and 

 both are adaptable to a greater range of conditions. How- 

 ever, some slight effect can be traced even in these higher 

 groups. The wood rat, for instance, is certainly confined to 

 the Piedmont, and the red squirrel seems not to venture 

 much beyond. The woodchuck, chipmunk and otter are more 

 at home in the Piedmont, while among the shrews, Micro- 

 sorex, so far as known, occurs only on the Piedmont and 

 Sorex fontinalis only in the Coastal Plain. 



The birds which as breeding species appear to respond to 

 the differences in conditions on the two great divisions of 

 our area are for the Piedmont: Nighthawk, Worm-eating 

 Warbler, Kentucky Warbler and Bewick's Wren; and for the 

 Coastal Plain : Florida Gallinule, Least Bittern, Bank Swal- 

 low, and Long-billed Marsh Wren. 



Among batrachians and reptiles Siren lacertina, Hyla 

 evittata, Coluber guttatus, Lygosoma laterale and Malaclem- 

 mys centrata belong to the Coastal Plain, while Spelerpes 

 longicaudus, Coluber obsoletus, Crotalus horridus and Clem- 

 rays insculpta are Piedmont forms. 



. The influence of the fall line on the distribution of abor- 

 iginal men and its control over city-building and the indus- 

 tries of modern man are interesting topics concerning which 

 the following is quoted from McGee : "Through the Potomac 



