No. 471] CRETACEOUS PLANT REMAINS 193 
good state of preservation especially when charred, or partially 
charred. 
Sectioning and Microscopie Examination of Specimens.— In 
the case of lignitic or charred vegetable remains it is necessary 
for successful study to obtain very thin sections, on account of the 
dark color and opacity of the fossilized tissues. By the use of 
hydrofluoric acid for removing mineral matter and by embedding 
in thickened celloidin, it was found possible to make sections 
often of large area, as thin as 5 micra which proved admirable 
for photomicrographic purposes. These sections were cleared 
at once in benzole without previous staining, since the natural 
dark color of the lignites was sufficiently pronounced to differ- 
entiate the structures, even in very thin sections. In some cases 
it was found necessary to reduce the natural dark hue of the prepa- 
rations and chlorine water was useful for this purpose. The 
sections were mounted in balsam on plate-glass slides and after 
previous drying were subjected to pressure and high temperature 
in the warm oven for the purpose of making them perfectly flat. 
All the photomicrographs in the present article were made by 
means of Zeiss lenses, except those showing surface features. 
The latter were executed with the admirable Heliar lenses of the 
Spencer Lens Co. Electric light was employed in all cases as the 
illuminant. 
DESCRIPTIONS OF SPECIMENS 
Cone Scales Commonly Referred to Dammara. — Fossil cone 
scales similar to ours were described and figured for the first time 
by Professor Edward Hitchcock,’ in his account of the organic 
remains found at Gay Head, Martha’s Vineyard. They were not 
named by him, but his figures and description leave little to be 
desired. He says: “Figs. 4, and 5, represent different individuals 
of another variety of vegetable remains....These are not mere 
impressions; but a scale of carbonaceous matter, mixed with 
amber, marks the spot where the vegetable was imprisoned... -It 
seems to me very obvious that these remains must be the seed 
vessels of some coniferous plants.” 
* Final Rept. Geol. Mass., vol. 2, p. 430, pl. 19, figs. 4, 5, 1841. 
