316 Proceedings of Societies. . [May. 
Dr. Engelmann remarked that the preservation of bones depends 
upon humidity and the character of the soil. Many bones undoubtedly 
older than the bones of these mound-builders are found ina state of 
good preservation. 
Dr. Engelmann made a communication on North American Oaks. 
The genus Quercus is more extensively developed in America than 
in any other part of the world. In the Carolinas, oaks grow as small 
shrubs. The leaves of different oaks show great variation, some re- 
sembling the leaves of the willow, others those of the holly, etc., but 
the fruit is very much the same in all. The typical and probably the 
primitive oak of the tertiary had an acorn and a lobed leaf. An oa 
found in California has flower and leaves like a chestnut, but bears 
acorns like an oak. The cup of the acorn, however, is spiny like the 
burr of the chestnut. Dr. Engelmann remarked that this oak may bea 
hybrid produced between the chestnut and the oak in bygone times when 
these genera were less differentiated, as it is well known that even now 
hybrid oaks will propagate when removed from the “ struggle for exist- 
euce” against more hardy rivals. 
ACADEMY OF Sciences, New York. — March 13th. The following 
papers were read: Further Researches on Phosphide of Silver, by Wm. 
Falke; A new Test for Boracic Acid, and other Qualitative Reactions, 
by M. W. Iles; Comparison of the Milk of the African Race with that 
of the Caucasian, by Henry A. Mott, Jr.; Milk and the Lactometer, by 
Elwyn Waller. 
Geological Section. March 20th. Mr. S. W. Ford presented an pa 
count of the discovery of additional species of fossils in the primordial 
rocks of Lansingburgh, N. Y., and of plant-remains in the primordial 
slates at Troy, and described a new species of Microdiscus from the 
latter locality, for which he has proposed the name, M. Meeki. He also 
exhibited specimens of the hitherto imperfectly known pygidium of 
Conocephalites (Atops) trilineatus, from Lansingburgh. In conclusion 
he made some remarks upon the probable stratigraphical horizon of the 
Troy beds among primordial rocks, stating that the fauna of these beds, 
while entirely distinct in its species from that of the Acadian or Mene- 
vian group on the one hand, and from that of the ordinary Potsdam on 
the other, yet shows a decided leaning, in its genera, toward the former 
of these groups. 
The president, Prof. J. S. Newberry, gave a résumé of his observa- 
tions on the geology of the oil regions of the United States, — all 0 
which he had visited, —and the results of his study of the facts which 
seem to illustrate the genesis of petroleum. ae 
Very briefly stated, his theory of the origin of petroleum is that it » 
one of the evolved products of a spontaneous decomposition of organie 
tissue, chiefly vegetable, which begins as soon as life ceases, and ends 
only with the oxidation of all the contained carbon and hydrogen. When 
