40 REPORT 01<^ NEW JERSEY STATE MUSEUM. 



proper understanding of its nature involved a thorough knowl- 

 edge of the plants of the contiguous areas w^hich, together with 

 it, constitute the coastal plain section of the state. Furthermore, 

 as it is necessary in a detailed study of distribution to have some 

 definite boundary line, the limit above mentioned was selected. 

 While this does not exactly coincide with the upper edge of the 

 coastal plain, it comes quite close to it and does not include any 

 of the higher ground above the fall line. 



The coastal plain extends north of Burlington and Monmouth 

 Counties to a line connecting Trenton and Bound Brook, thence 

 to Passaic and Hackensack behind the Palisades, and includes 

 all the low country adjacent to the Hackensack marshes as well 

 as Staten Island, part of Long Island and the immediate coast 

 district of southern New England. In New Jersey this involves 

 parts of Mercer, Middlesex, Union, Hudson, Essex, Passaic 

 and Bergen Counties, and, while the ranges of many southern 

 New Jersey plants touch them all, the higher parts of these 

 counties harbor so many northern plants that to include them 

 would be confusing. Moreover, no southern plants occur in this 

 northern extension of the coastal plain which do not also occur 

 south of our boundary line. 



This coastal plain region of New Jersey has always attracted 

 the attention of naturalists because of the striking differences 

 that are presented by its flora and fauna as compared with those 

 of the higher ground of the Piedmont country to the north and 

 w^est of it. Pennsylvanians often liken it to a bit of the Southern 

 States that has been transported northward. Its climate in winter 

 is certainly milder; there is rarely a heavy snowfall, and what 

 does fall soon disappears, while many southern species of plants 

 and insects and a few birds and mammals are found there which 

 are unknown to the w^est of Philadelphia or elsewhere beyond the 

 fall line. 



It may seem incongruous to find a "southern flora and fauna" 

 by going eastward, as w^e do in the vicinity of Philadelphia, but 

 this is easily explained when we examine a map of the life zones 

 of North America. As Dr. Merriam has shown, temperature is 

 one of the chief — if not the chief — factors in fixing the bound- 

 aries of these zones. If the surface of the earth were level, they 



