1888. | NEW YORK ACADEMY OF SCIENCES. 163 
Mr. Kunz suggested that the famous ‘* Leyden plate” found 
in 1875, and the ‘“‘ Humboldt celt,” obtained by Humboldt, in 
1803, from Sr. Del Rio, and now in Berlin, were probably parts 
of one large celt, from which other pieces might also have been 
taken. The dark-brown color was probably produced by heat. 
There is no record of jadeite being found im si¢w on this con- 
tinent, the only known locality being Burmah. 
PRESIDENT NEWBERRY thought it not improbable that the 
jadeite found fashioned into ornaments at many localities in 
America and Europe, was of eastern origin. It seems to have 
been regarded as a substance of inestimable value, a badge of 
royalty, and to have passed from hand to hand forages. Its oc- 
currence in Mexico suggests communication between the Old 
and New Worlds, more probably by way of the East Indies. 
Mr. Kunz also exhibited a new form of oligoclase, trans- 
parent and glass-like, from near Bakersville, N. C. It contains 
white, stellated inclusions, similar in form to those observed 
in the Ceylonese moonstone; but, while the latter are crystals, 
the former are merely hollow spaces. He also announced that 
he had identified spessartite garnet, from Amelia Court House, 
Amelia County, Va. In color hyacinth, light-brown and dark- 
brown. 
Pror. J. S. NEWBERRY gave an address upon 
THE PROGRESSIVE DEVELOPMENT OF THE MEANS OF ATTACK 
AND DEFENCE IN FISHES. 
(Profusely illustrated with specimens and lantern views. ) 
April 16, 1888. 
STATED MEETING. 
The President, Pror. J. S. NEWBERRY, in the chair. 
Thirty-two persons present. 
Mr. WitirAm L. ELserrer presented the following :— 
