xxii M. Brongniaut's Table of Mixed Rochs. 



Species 4. BRECCIA.* 



A rock priacipally composed of angular, uncrystallized 

 middle sized fragments, agglutinated by a paste. 



Principal varieties. 



Qdartzose B Fragments of quartz and other rocks united 



by a serpentine paste. 

 (Col de Queyriere, in the Brian^onnais.) 

 Schistose B Fragments of schist, phyllade, &c. in an ar- 

 gillaceous paste. 

 (Todt-liegende of Eisenach. — ^The coast near 

 Saint Jean de Luz. — Coutance.) 

 Schisto-Calcareous B. Fragments of schist or other argillaceous 

 rocks, in a more or less calcareous paste. 

 (Environs of Elbingerode in the Hartz. — 

 Braunsdorf in Saxony.) 



Calcareous B Calcareous fragments in a calcareous paste. 



Volcanic B Fragments of pyrogenic (pyrogenes) rocks en- 

 veloped in a calcareous, argillaceous paste 

 of wacke, lava, &c. 

 . ' (Aurillac. Gergovia. Habichtswald in Hesse. 



— Rome.) 



* There are no precise limits between some puddingstones and some 

 breccias, but there are so many important differences between siliceous 

 puddingstone and calcareous breccia that we can, on no account, unite 

 these two rocks in the same species. 



