CHARACTERISTICS OF THE FLORA. 27 
This experience caused us great disappointment, and I became nearly 
hopeless of being able to accumulate such representatives of the Amboy 
‘lay*flora as would suffice for careful and deliberate study, and, what was 
of primary consequence, should remain as types and standards for future 
comparison. Nothing has contributed more to the confusion and uncer- 
tainty that has prevailed in the literature of natural history than the loss 
of type specimens, and no solid and substantial progress could be made in 
the study of this flora if the material were to perish in the using. 
The truth of this statement is abundantly proved by the uncertainties 
that hang over the first efforts to investigate this flora. The fossil plants 
collected by Professor Cook were submitted to Mr. Leo Lesquereux, of 
Columbus, Ohio, the eminent paleobotanist, and his report upon them is 
given on page 27 of the Report on the Clay Deposits of New Jersey, 
which forms one of the reports of the Geological Survey of the State, 
issued in 1878. His report will be referred to in detail on another page. 
It begins as follows: “The specimens, very numerous, badly preserved, 
from Sayreville and other localities, have, * * * * so far as they 
are determinable, the characters of the flora of the Dakota group.” He 
attempted, however, to determine the species, and reports a list which I 
shall give further on. The material submitted to him I had an opportunity 
of examining, and, as before stated, found it to be practically worthless. 
At this stage of our experience, and when we were much discouraged 
in our efforts to gather and study the remains of the clay flora, Dr. Britton 
fortunately discovered at South Amboy a layer of the clays in which the 
leaf impressions carried very little carbonaceous matter—simply enough to 
color the area of the leaf with a coftee-brown tint. These impressions we 
found to be permanent, and since that time our efforts have been mainly 
directed to the discovery of such layers in this and other clay pits and the 
gathering of material of this kind. A similar layer was discovered by Mr. 
I. H. Woolson at Woodbridge, and this has furnished perhaps three-fourths 
of all the specimens which are figured and described in this memoir. From 
Sayreville we have as yet obtained no leaf impressions of this character, 
and the treasure which there lies entombed is for the most part intact, and 
we must discover some method by which the specimens from this locality 
