326 Scientifie Intelligence. 
geological maps received by him from several of its members. 
In these reports the recommendation from the Swiss Committee 
clear yellow for Piinodne and ver ite" gr en for otiatarbar! 
For i iluri i h i 
have osed but one ae Py that the countries contain 
little Bf either of these fo 
2. Geological terms Per "Stratigraphicel Subdivisions.—Lookin 
at the earth’s strata as a histor gh series, it becomes natural to 
iia geological time into ages eras, eriods and: ¢ ochs. 
formation or system. The word terrane, from the French terrain 
and eae’ terreno, has been employed, but without defined 
restrictio 
cation of the terms use rench and Belgian works on hn 
namely, formation, serves , systeme, étage, assise, zone, couche. Le 
cites D’Archiac’s protest in 1847, against the confusion as to their 
use at that time in France, and shows that the confusion is hardly 
ence is to be made to rocks o nd as caleareous formations, 
granitic formations; and bite as the best terms and their best — 
order, commencing with that of broadest signification, Rite 
8) ystem, » wage, substage, the last, made synonymous with “ assise,” 
and group; adding that the terms series rp zone (the tbat when 
characterized by particular fossils), may times be used w 
convenience, though not made to iitin gaia any partioulkt gra 
of subdivision. 
jolite)’ ane each of these systems contains e to four stages, 
e. g., for the Portlandian system the three stayes, Purbeckian, 
Portlandian and Kimmeri ridigian ; and so on 
