A NEW MACROSTACHYA FROM THE 
CARBONIFEROUS OF [ILLINOIS 
BY 
WinniamM C. Darran 
ALTHOUGH an extensive literature concerning cala- 
marian cones has been developed during the past fifty 
years, only meager information about Macrostachya is 
available. Well-preserved specimens of cones of fossil 
plants are rather rare, and frequently the fragmentary 
nature of larger forms makes investigation difficult. Mac- 
rostachya belongs to articulated plants remotely related 
to living Equisetales. 
The specimen described in this study was collected 
in the strippings of the Wilmington mines, Will County, 
Illinois. These coal workings are an extension of the 
‘*Mazon Creek’’ beds. The specimens occur in typical 
iron-stone nodules. Mr. Frederick O. Thompson, the 
collector and donor, has presented his extensive collec- 
tions to the Botanical Museum of Harvard University. 
Mr. Thompson has succeeded in gathering 11,000 speci- 
mens from Will County, and although calamarian cones 
are relatively common only two are referable to Macro- 
stachya. 
The complete specimen, number 15602, was. first 
studied in the round, and then investigated by the ‘‘peel”” 
method. 
This peel method may be described briefly. The sur- 
face of the specimen is washed carefully with water and 
then is etched with a two percent solution of hydrochloric 
acid. Following the application of acid, the surface is 
again washed with water in order to remove excess acid 
and salts in solution. After the specimen is dry, a solu- 
tion of nitrocellulose in buty] acetate is poured over the 
etched surface. Within six hours the nitrocellulose hard- 
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