Dr. Du Riche Preller — The Carrara Marble District 561 



as far as Miseglia, about 1 kilometre north of Carrara, at which point 

 begins the sequence of the Triassic and older rocks. From here, at 

 altitude 240 metres — and about the same level in the other divisions — 

 the succession, omitting the minor alternations — may be summarized 

 as follows: — 



MESOZOIC. *%££ 



I. Upper Trias. 1. Upper Schist, Marble, and Limestone Zone. 



(a) Upper Schist, sericitic and chloriticA 



with pseudomacigno sandstone . . ! „„« 



(b) Cipollini and Upper, cavernous Grezzoni, j 



semi-crystalline and dolomitic . . J 



(c) Upper Marble, white, statuary, bardiglio, 



veined, and breccia .... 300 



(d) Banded and Nodulous Limestone, grey 



and yellowish ..... 200 



2. Principal Marble 'Zone, white, statuary, 



bardiglio, veined, and breccia . . . 1,000 

 II. Middle Trias. 1 Principal Grezzoni Zone, dolomitic, semi- 

 crystalline, dark-grey, brown, and whitish 

 limestone ....... 500 



PALEOZOIC. Central Schist Zone, dark grey, micaceous and 



III. Lower Permian. gneissose, with calcareous, talcose schist 



intercalations . . . . . . 1,000 



3,300 

 It is thus seen that the upper and the principal saccharoidal marble 

 zones together represent a visible depth of no less than 1,300 metres, 

 over three-quarters of a mile. As shown in Figs. I to IV, the normal 

 sequence of strata is uniformly the same throughout the three main 

 divisions of the district, the marble of the principal zone resting 

 normally always on the principal grezzoni beds, and underlying the 

 banded and nodulous limestone of the upper series, except in abnormal 

 or reverse flexures. The strata of the upper series frequently alternate 

 with each other, as shown in Fig. II ; hence the marble of that series 

 is always associated with one or more strata of that zone. 



V. The Central and the Uppee Schists. 

 The central schists constitute the lowest formation and the nucleus 

 of the range, and round and above them appear concentrically all the 

 successive Triassic series. These central schists were formerly 

 regarded variously as of Archaean, Silurian, or Carboniferous age ; 

 but the discovery in 1880 by Lotti and Zaccagna of abundant 

 Orthoceras and Antinocrinus fossils in the frequent calcareous schist 

 intercalations, notably near Fonte Mosceta in the depression between 

 Monte Corchia and Pania della Croce in the Versilia (Stazzema) 

 division (vide iTin Fig. Ill), enabled Professor Meneghini of Pisa to 

 assign the central schist formation definitely to the Palaeozoic. 2 



1 The Lower Trias is, in the Apuan Alps, so sparsely represented by a coarse 

 sedimentary conglomerate underlying the Middle Trias grezzoni at a few 

 isolated points of the range, e.g. near Vinca, Pizzo d'Ucello, and in the Ami 

 region, as to be negligible. The conglomerate marks a transition from Upper 

 Permian to Trias. 



2 "Nuovi Fossili delle Alpi Apuane " : Proc. Verb. Soc. Tosc. Scienze 

 Naturali, November 14, 1880. 



DECADE VI. — VOL. II.— NO. XII. 36 



