334 



THE BUNTEK-SAJSTDSTELN. 

 a Fig. 426. 5 



[Ch. XXIL 



Ceratites nodosus. Muschelkalk. 

 a. Side view. 6. Front view. 



c. Partially denticulated outline of the septa dividing the chambers. 



bivalve shells, the Posidonia minuta, Goldf. (Posidonomya minuta, 

 Bronn) (see fig. 426), is abundant, ranging through the Keuper, Muschel- 

 kalk, and Bunter-sandstein ; and Avicula socialis, fig. 427, having a 

 similar range, is very characteristic of the Muschelkalk in Germany, 

 France, and Poland. 



Fig. 426. Fig. 427. 



Posidonia minuta, a. Avicula socialis. b. Side view of same. 



Goldf. (Posido- Characteristic of the Muschelkalk. 



nomya minuta, 

 Bronn.) 



The abundance of the heads and stems of lily encrinites, Encrinus 

 Fig. 428. liliifonnis, fig. 428 (or Encrinites moniliformis), show 



the slow manner in which some beds of this limestone 

 have been formed in clear sea-water. The star-fish 

 called Aspidura loricata (fig. 429) is as yet peculiar 



Fig. 429. 



Encrinus liliifonnis, Schlott. Syn. E. moniliformis. 



Body, arms, and partof stem. 



a. Section of stem. 



Muschelkalk. 



Aspidura loricata, Agas. 



a. Upper side. 



b. Lower side. 

 Muschelkalk. 



