48 J. Schiel on Classification by Series. 
The plant-bearing sandstone of Phoenixville Tunnel, though 
not containing all the genera of plants found in the Mangali 
strata, is far richer in Saurian remains. Crustaceans (Estherias 
and Cypris) parts of ganoid fishes, and shells. The green shales 
of the Tunnel have worm tracks, and the intestine shaped evac- 
uations. The bituminous shales are rich in organic remains. 
The remains of Conifers, Zamites, Hquisetites and probably 
fruits and seeds, with dolomitic sandstones, indicate a very great 
similarity with the lower Jurassic Central Indian formation. 
Pheenixville, Penn., Feb. 1861. 
ART. 5 a the Classification of Organic Substances by Series ; 
by James ScuHIEL, of St. Louis. 
The general formula of organic compounds containing carbon, 
hydrogen and oxygen is €,Hg@._By giving to y successively 
the values 1, 2, 3, 4,... we may form the following series o 
oxydation : 
(A) €aHgO 
€,Hp0, 
€.Hs9, 
From this all the series necessary for the classification of or- 
ganic substances may be derived by putting «=n and §=2n+2, 
making # successively to decrease, the decrement being 2, 4, 6, 8, 
* Annal, Liebig and Wohler, July number, 1842. t . 
+ Gerhardt changed the name progressive into homologous, in the discovery 
itself of the series he has no share 
