236 Chemical Composition of Recent and Fossil Lingule. 
From the color it is probable that the iron exists as a carbon- 
ate. When heated in a tube, a strong odor like burning horn is 
perceived, accompanied by ammonia which reddens turmeric pa- 
er and gives white fumes with acetic acid, showing that a part 
at least of the volatile matter is of an animal nature. The spe 
cimens from Lac des Allumettes lose 1-7 p. c. by gentle ignition, 
with a like production of ammonia, and an odor of animal mat 
ter; the same thing was observed with those from Grenville. 
he existence in Lower Silurian rocks, of these masses, whose 
characters leave no doubt that they are coprolites, and whose 
chemical composition is like that of the excrements of creatures 
feeding upon vertebrate animals, led us to examine the shells of 
the Lingule always associated with these phosphatic bodies. ‘T 
result has beeu that all the specimeus yet examined consist chiefly 
_of phosphate of lime; they dissolve readily with slight efferves- 
cence in hydrochloric acid, and the solution gives with ammonia 
a copious’ precipitate readily soluble in acetic acid, from which 
oxalic acid throws down lime. With a solution of molybdate of 
aminonia there is obtained a quantity of the characteristic yel- 
low molydo-phosphate, many times greater than the bulk of the 
shell. 
We have thus examined Lingula prima, and L. antiqua, from 
the Potsdam sandstone, Z. parallela from the calciferous, and a 
species somewhat resembling L. guadrata, from the ‘Trenton 
limestone. It was desirable to compare with these, the shell of 
a recent specics. and for this purpose, fine specimens of the Lin 
gula ovalis, of Reeve, from the Sandwich Islands, were farnished 
us by J. H. Redfield, Esq. of New York. The shell of this spe 
cies had the same composition as the fossil ones, and the thick 
green epidermis, which swelled up like horn when heated, ga¥¢ 
a buiky white ash of phosphate of lime. 
For a further analysis the shell was boiled in water to remove 
all soluble matters, the soft parts still adherent were carefully de 
been concentrated, the phosphoric acid was thrown down by @ ; 
grms. © 
pyrophosphate of magnesia, equal to 044 of phosphoric acid, oF 
‘U978 of phosphate of lime, PO;,3CaO. 
The lime was separated from the acetic filtrate, as an oxalat®s 
and gave “1US of carbonate, equal to -0605 of lime, being 4” a 
