7a SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 63 
considerably, as shown in figure 16, but the even skyline of the ancient 
plain is still clearly evident. 
Other factors in the geologic history of Maryland are recorded in 
the well defined gravel terraces along the major streams of the area 
and in great alluvial fans of large and small bowlders, spreading out 
at the foot of the larger mountains and sometimes reaching a depth 
of 150 feet. All of these phenomena have been plotted and will 
forma part of the geologic map of the region. 
Fic. 16.—Dissected Early Tertiary (Harrisburg) peneplain, west of Hagers- 
town, Maryland. Photograph by Bassler. 
COLLECTING FOSSIL ECHINODERMS IN ILLINOIS 
The special field explorations maintained by Mr. Frank Springer, 
associate in paleontology in the U. S. National Museum, were con- 
tinued during the season of 1913 by his private collector, Frederick 
Braun. The purpose of these explorations is to obtain additional 
material for use in Mr. Springer’s monographs upon the fossil eri- 
noidea, now in course of preparation, but they also result in important 
accessions of excellent specimens for the completion of the exhibt- 
tion series in the hall of Invertebrate Paleontology in the National 
\luseum, 
