1893. ] NEW YORK ACADEMY OF SCIENCES. 237 
MAPS, ETC., USED. 
Geological Map of the United States, published in connection with the 
9th U. S. Census, by C. H. Hitchcock and E. P. Blake. 
Geological Map of New Jersey. Rept. Geol. Sury. of N. J., 1882. 
Geological Map of the Vicinity of New York, by D.S. Martin. 
Coast Survey Chart No. VIII. Approaches to New York. Gay Head 
to Cape Henlopen. 
The Ancestors of the Tulip Tree (Plates LXI. and LXIJ. Bull. Torr. 
Bot. Club, Jan. 1887) by J. S. Newberry. 
Flora Fossilis Arctica, Vols. VI. and VII, (Plates representing the fos- 
sil flora of the L. Atane and Patoot beds), by Oswald Heer. 
United States Geological Survey, Vol. VI. (Cretaceous Flora), by Leo 
Lesquereux. 
SPECIMENS SHOWN. 
White and colored clays, pyrite nodules and lignite. Glen Cove, L. I. 
Plant remains in clay. Northport, L. I. 
Plant remains in sandstone, from the drift at Brooklyn, L. I. 
Plant remains in concretions, from the drift near Glen Cove, L. I. 
Plant remains in red shale, from clay outcrop on the shore near Glen 
Cove, I. 
ON ANTENNA AND OTHER APPENDAGES OF TRI- 
ARTHRUS BECKII. 
BY W. D. MATTHEW. 
(Plate VIII.) 
Among the problems which paleontologists have in vain tried 
to solve was, till a few years ago, that of the structure and 
affinities of the trilobite. In all the vast numbers of these ani- 
mals which have been found and studied, scarcely any parts 
have been preserved, other than the dorsal shield and hypostome. 
The legs, gills, ete., have practically never been shown on any 
specimen, This is chiefly because of the easy break afforded 
by the hard, smooth carapace, but, partly also, because of the 
character of these organs, which seem to have been soft, easily 
disjointed, and prone to maceration and decay. The only cases, 
as far as I know, in which the organs of the under side have 
been definitely seen and described, are three specimens of 
Asaphus platycephalus in which a number of legs are preserved 
