GEOLOGICAL HISTORY OF SERPENTINES. 191 
stratified serpentines, quartzites, often sandstones, argillites, dolomites, micaceous lime- 
stones, and banded and statuary marbles. This group. as we have already indicated, pre- 
sents many resemblances with the great Lower Taconic or Taconian series of North Ame- 
rica. In it are included by Gastaldi, the crystalline limestones of the Apuan Alps, which 
yield the statuary marbles of Carrara and of Massa. 
§ 70. In the Western Alps there is, so far as is known, no evidence of lower-paleozoic 
rocks, the sandstones with anthracite, which succeed the crystalline schists, containing in 
many places a carboniferous flora. The same, according to Gastaldi, is true in the Maritime 
Alps and the Apennines, where, in many cases, he finds the crystalline schists overlaid by the 
anthracitic series. Thus in the valley of Macra, above the serpentines are found calcareous 
schists with crystalline limestones and quartzites, which are successively overlaid by the 
carboniferous sandstones, the limestones of the trias, with their characteristic fauna, the 
lias, the cretaceous and the nummulitic beds. At Torre Mondovi, the serpentines are over- 
laid by fossiliferous triassic limestones, while in the valley of Bormida they are directly 
succeeded by the marls, sandstones and conglomerates of the lower miocene, and in the 
valleys of Staffora and Polcevera by the alberese and the macigno of the eocene. The supposed 
pre-carboniferous fauna fouud by Michelotti in the limestones of Chaberton, has, on fur- 
ther examination by Prof. Meneghini, been shown to be of triassic age. * 
§ 71. Passing now from the mainland of Italy, we come to Corsica and Elba. The ser- 
pentines of the former island have lone been known to geologists, and have within the last 
few years been especially studied by Hollande, Coquand, Dieulefait and Lotti Coquand, 
who described the serpentines of Corsica in 1879, and who, like Hollande, regards them as 
eruptive, supposes them to be in part very ancient, and in part tertiary, since according to 
him, some of them overlie the nummulitic beds. | Pellati, whose essay we have already 
cited, refers however the whole of the serpentines of this island to a pre-paleozoic period, 
and Dieulefait, who described these rocks in 1880, ¢ declares that Coquand’s reference of 
the serpentines found near Corte to the tertiary is based on an error of observation. He 
moreover asserts that the serpentines of Corsica are stratified sedimentary rocks belonging 
to a single geological horizon, at which they may be traced continuously for a length 
of more than 200 kilometres from Corso along the northeast coast of the island. The geo- 
logical succession, according to him, is as follows :—1, stratified protogine ; 2, gneiss ; 3, 
lustrous schists; 4, saccharoidal limestones ; 5, schists more or less talcose; 6, schists 
enclosing serpentines of many varieties ; 7, clay-slates; 8, black limestones with carbona- 
ceous matter ; 9, beds often detrital ; 10, infra-liasic limestones, with Avicula contorta. 
§ 72. Lotti, who has since studied these rocks, $ confirms fully the observations of 
Dieulefait. He describes the crystalline limestones, white or banded, with grayish, greenish 
or lead-colored talcose or silky schists, holding a mica, sometimes apparently damourite or 
sericite, in which are found layers of serpentine. The serpentine itself is generally scaly 
in texture and glassy, but granular varieties are met with including veins of epidote, others 
with altered crystals of olivine, and also ophicalcites. The gneisses beneath the serpentine- 

* Gastaldi’s letter to Zezi, in 1878, already cited. 
+ Coquand. Bull. Soc. Géol. de France, (3) vii. 
{ Dieulefait. Comptes Rendus de l’Acad. des Sciences, xci., p. 1000. 
4 Lotti, Appunti Geologici sulla Corsica ; Boll. del Comitato Geologico, anno 1883, No. 3-4. 
