ZONE OF AEGOCERAS PLANORBIS. 



25 



Museum. The A. planorbis of the Lias a, near Tubingen, very much resembles the 

 variety of this shell found clustered together in blocks washed out of the Scar at 

 Robin Hood's Bay. One of the finest specimens of this locality, in the Leckenby Collec- 

 tion, Woodwardian Museum, Cambridge, I have figured as typical of the species. 



In Baden the Planorbis-beds are found in the Langenbriicker Jura resting upon the 

 Bone-bed Sandstone of the Contorta series, and containing shells and fishes' remains 

 similar to those found in England. The lovt^er Lias begins at Malsch and Oestringen 

 with a 2-foot bed of black-blue Limestone containing Aegoceras planorbis. The Angu- 

 LATUM zone appears to be absent, for the Planorbis-bed is overlain by clay containing 

 Gryphoea arcuata and Eucoids, upon which rests the BucHandi-series. 



In France this zone is well developed in the department of the Cote d'Or, as proved 

 by the following list of fossils obtained from the Lumachelle de I'Auxois,^ and contained in 

 the well-arranged Museum of Semur, all of which I had the advantage of studying under 

 the polite guidance of MM. Collenot and Breon, to whose scientific knowledge, judgment, 

 and good taste, this fine local collection owes its well-merited reputation. 



Reptiles. 



Ichthyosaurus, sp., at Beauregard, Semur. 



Fishes. 



Saurichthys acumiDatus, Agass. 



Aegoceras planorbis, Sow. 



— Johnston!, Sow. 



— tortile, cl'Orb. 



I Sargodon tomicus, Plien. 



Cephalopoda. 



Aegoceras Prometheus. 



— laqueus, Quenst. 



— Burgundise, Mart. 



Chemnitzia Phidias, d' Orb. 

 Neritina cannabis, Terq. 

 Littorina clathrata, Desk. 

 Turritella Deshayesei, Terq. 



Gasteropoda. 



Pleurotomaria, sp. 

 Cerithium, sp. 

 Orthostoma, sp. 

 Turbo, sp. 



Lamellibranchiata. 



Pleuroraya crassa, Agass. 



— striatula, Agass. 

 Pholadomya prima, Quenst. 

 Goniomya Sinemuriensis, O^yj. 

 Anatina Sinemuriensis, Mart. 

 Leda tenuistriata, Piett. 

 Astarte Geuxii, d'Orh. 

 — cingulata, Terq. 



Cypricardia compressa, Terq. 

 Cardita tetragon a, Terq. 

 Cardinia Sinemuriensis, cCOrh. 



— Deshayesei, Terq. 



— quadrangularis, Mart. 



— Moreana, Mart. 



— crassiuscula, Sow. 



— trapezium, Mart. 



' J. J. Collenot, ' Description Geologique de I'Auxois,' p. 209. 



