Six amber specimens from Kreischerville were run 
from Harvard Botanical Museum Paleobotanical Collec- 
tion #52812. All of the spectra were similar to that shown 
in H 821 (Plate XIV). Thus, the possibility of two 
sources did not become evident in the particular samples 
analyzed. The similarity of the spectra from Kreischer- 
ville and from the Koalak Riverin Alaska is noteworthy. 
Although stratigraphic data for the Kreischerville de- 
posit have not recently been critically assessed, it appears 
that the amber here is probably only slightly older (Ceno- 
manian) than the Koalak amber (Senonian). Although 
a taxodiaceous source is strongly indicated for at least 
part of the amber in both localities, infrared spectra of 
modern resins of representatives of this family have not 
as yet provided corroborative evidence. This has been 
true for the Pinaceae as well. 
Magothy River Amber 
Troost (1821) described amber associated with lignites 
at Cape Sable, Magothy River, Anne Arundel County, 
Maryland. These are the strata which later were desig- 
nated as the Magothy Formation (Little, 1917). Troost 
indicated that this amber occurs generally as grains ‘“from 
the size of a mustard seed to that of pieces from 4 to 5 
inches in diameter.’’ Most of it is opaque, varying from 
brown to yellowish grey; transparent specimens seldom 
are found. Also some of it is ‘‘earthy’’, occurring as 
friable, porous masses. 
Although Troost was interested in the kind of wood 
with which the amber was associated, he was unsuccess- 
ful in identifying the lignites. Knowlton (1896), how- 
ever, found at this locality a log which contained small 
pieces of amber. Poor preservation of wood and its ten- 
dency to disintegrate with exposure left its generic deter- 
mination open to question. Knowlton finally concluded, 
[ 81} 
