X PREFACE. 



rock, gravel, clay and sand, and this glacial drift soil extends as 

 far south as a line running irregularly from Perth Amboy, at 

 the mouth of the Raritan river, to Belvidere, on the Delaware 

 river. The region north of this line has a decidedly northern 

 Flora, over one-third of all the species growing wild in it 

 being natives of Europe, and a large number of the others being 

 only found further north on our own continent. 



The southern part of the State is very unevenly covered with 

 a deposit of light-colored sand and gravel, with quartz pebbles, 

 whose origin is still uncertain. This is the " Yellow Drift," * 

 frequently referred to in the following pages. 



In this part of the State the northern Flora is meagre, and 

 twenty mileg south of a line drawn from Perth Amboy to Tren- 

 ton, is reduced to less than five per cent, of European species 

 with perhaps an equal number of northern North American 

 plants, and is replaced by an abundant truly American Flora 

 which is peculiar to this continent. These southern North 

 American plants are in a like manner but sparingly represented 

 on the glacial drift. The region included by these two diverg- 

 ing lines and the Delaware river, appears to possess a mixed 

 Flora, the northern species being found to some extent on the 

 mountainous portions of it, and the southern on less elevated 

 parts ; which of these Floras is in excess, is yet to be determined, 

 but there are certainly many southern species there. Hence we 

 may in general conclude that the terminal glacial moraine is the 

 dividing line between the northern and southern Floras of New 

 Jersey. 



In the work of compilation, my thanks are due to Mr. C. F. 

 Parker, of Camden, for exceedingly valuable assistance — he 

 kindly sent me catalogues of the New Jersey plants contained in 

 his herbarium, and compiled lists of the Mosses and Liverworts 

 from the collections of the late Coe F. Austin; to Mr. J. B. 

 Ellis, of Newfield, for the Catalogue of Fungi ; to Rev. Francis 

 Wolle, of Bethlehem, Penna., and Rev. A. B. Hervey, of Taun- 

 ton, Mass., for lists of the Algse ; to Dr. T. F. Allen, of New 



*See Annual Report of State Geologist for 1880, on the pre-glacial drift, pp. 87-97. 



