1893.] Geology and Paleontology. 149 
Geological News, General.—Mr. R. S. Tarr has published a 
paper in the Am. Geol., July, 1892, calling attention to the relation of 
secular decay of rocks to the formation of sediments. The essay is in 
the main a summary of the present knowledge of secular disintegra- 
tion. The rocks of the Guadalupe Mountains are referred by 
R.S. Tarr to the Upper Coal Measures instead of the Permian as 
determined by Shumard. Bull. No. 3, Geol. Surv. Texas——A Geo- 
logical and Agricultural Survey of the State of Louisiana has been 
undertaken in the interest of agriculture, the first publication of which 
has just been issued. It consists of a preliminary report on the north- 
ern part of the State, by Dr. Otto Lerch, covering the Topography, 
General Geology, Water Supply, Distribution of Soils and Useful 
Minerals. M. Adolph Carnot states that the relative age of fossil 
bones can be ascertained by estimating the amount of fluoride of cal- 
cium entering into their percentage composition. His method was 
applied recently to determine whether a human tibia was contempora- 
neous with the bones of animals with which it was associated. The 
chemical analysis proved that the tibia contained only the same per- 
centage of fluoride as a recent human bone, while the associated animal 
remains vielded seven to nine times as much fluoride as their recent 
analogues. Hence the tibia in question belongs to a later period than 
the other fossils with which it was found, a result in which M. Riviére — 
acquiesces on other grounds.—Comptes- Rendus, Vol. exv, pp. 337-339. 
Archean.—Dr. Charles Barrois announces the discovery of Ra- 
diolaria in the Archean rocks of Brittany. The fossils occur ina fine 
siliceous matrix (phtanite) associated with fragments of graphite, in 
the neighborhood of Lamballe, Cotes-du-Nord. M. Cayeux, to whom 
the fossils were submitted, regards them as simple Radiolaria, of the 
family Monospheridee—Natural Science, Oct., 1892. - 
Paleozoic.—According to Dr. Riist, Radiolarian fossils are abund- 
ant in Paleozoic rocks, and nearly all of the Paleozoic Radiolaria can 
be referred to the genera recognized by Haeckel in the seas of to-day. 
—Palxontographica, Vol. xxxviii, pp. 107-200. 
Three me ai of fish—Protodus jexii, Diplodus problematicus, 
and Acanthodes semistriatus—have been added to the list of Lower 
Devonian Fish-fauna by Mr. A. S. Woodward. The fossils were col- 
lected by Mr. Jex at Campbellton, New Brunswick, and are now In 
the British Museum.—Geol. Mag., Jan., 1392. 
