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Chemical Composition of Recent and Fossil Lingule. 238 
and even the free upper part of the ovary. In all the Cered and 
Echinocacti examined by me, I find the lowest part of the tube 
free, the filaments being adnate to some distance above the ovary. 
Itis not improbable that the Chilian velvety Cerei ( Velutini, Pr. 
Salin.) are to be classed near our species. he flower of what 
appears to be Cereus Chilensis, Pfr., obtained near Valparaiso, and _ 
figured by the artist of the U. S. Exploring Expedition, greatly 
resembles that of C. Thurberi: it is a little larger, but has 
the same shape, and the same closely imbricated sepals on the 
ovary ; the tube has about 100 sepals, and the white petals are 
acute ; whether fleshy or not is uncertain. 
Arr, XXIV.—On the Chemical Composition of Recent and Fs- 
sil Lingule, and some other Shells; by W. E. Loean, F.R.S., 
and 'T.-S. Hunt. 
In the Report of Progress of the Geological Survey of Canada 
for 1851-52, we have mentioned the existence of small masses 
containing phosphate of lime, and having the characters of cop- 
rolites, which occur in several parts of the Lower Silurian rocks. 
In a bed of silicious conglomerate towards the top of the calcife- 
rotis sandstone, at the Lac des Allumettes, on the Ottawa, they 
are abundant in cylindrical and imitative shapes, sometimes an 
inch in diameter. The same material forms casts of the interior 
of a species of Holopea or Pleurotomaria, and often fills or com- 
pletely incases the separated valves of a large species of Lingula, 
which Salter has referred to L. parallela of Phillips. ‘The phos- 
phatic matter is porons, friable, and of a chocolate brown color; 
it contains intermixed a large quantity of sand; and small peb- 
bles of quartz are sometimes partly imbedded in it. The analy- 
sis of one specimen gave 36 per cent. of phosphate of lime, with 
P. ¢. of carbonate and fluorid, besides some magnesia and oxy 
of iron, and 50 p. ec. of silicions sand. 
_ Similar masses occur in the same formation at Grenville, and 
in the lower part of the Chazy limestone at Hawkesbury, in both 
cases containing fragments of Lingula.” Those from the latter 
place, are rounded in shape, and from one-fourth to one-half of an 
inch in diameter, blackish without, but yellowish-brown within, 
and having an earthy fracture; the analysis of one of them gave: 
Phosphate of lime, (P Os, 3Ca O), - 44-70 
Carbonate of lime, - -- - - 6 
Carbonate of magnesia, - - - 
Peroxyd of iron, and atrace of Alumina, 8°60 
Insoluble silicious residue, - - - 27 
Volatile matter, -  - - - ° 5-00 
