163 



Liniea acuticosta, Ooldf. Pecten priscus, Schloth. 

 Avicula longiaxis, Buck. " diversus, Buck. 



Monotis insequivalvis, Sow. " liasinus, Nyat. 



Inoceramus ventricosus, Soto. Gervillia Isevis, Buck. 



n substriatus, Ooldf. Plicatala spinosa, Sow. 



Pecten seqiiivalvis, Sow. Gryphaea cymbium, Lamh. 



Brachiopoda. 



Terebratula punctata, Sow. Rhyncbonella variabilis, Schloth. 



Spirifera rostratus, Schloth. Orbicula scaliforme, Wr. 



Ebyncbonella rimosa, von Buch. Lingula Beanii, Phil. 



ECHINODEEMATA. 



Cidaris Edwardsi, Wr. Opbioderma Gaveyi, Wr. 



Acrosalenia, Nov. Sp. Acroiira Brodiei, Wr. 



Pedina, Nov. Sp. Pentacrinus robustus, Wr. 

 Uraster Gaveyi, Fori. « punctiferus, Quenst. 



Tropidaster pectinatus, Fori. " subangularis, Mill. 



On the coast of Yorkshire, as at Staithes, Botilby, and 

 Skinningrave Bay, where the Middle Lias is largely developed 

 and finely exposed in magnificent coast sections, the shales 

 with Am. capricornus = Am. maculatus, form the base of the 

 cliffs. From Skinningrave Bay, I have specimens of Ophioderma 

 Gaveyi, and it was here that Plumaster ophiuroides, Wr., was 

 found, and from the same zone in Robin Hood's Bay, Luidia 

 Murchisonce, Will., was collected. On the Dorsetshire coast, 

 as near Charmouth, this zone forms the upper portion of the 

 grey micaceous marls, or "Green Ammonite bed" of the local 

 collectors. In this stratum a great number of very fine 

 Ammonites, with the shell well preserved, are found as Am. 

 capricornus, Schloth., Am. Loscomhi, Sow., Am. Jimhriatus, Sow., 

 Am. latoecosta, Sow., Am. Bechei, Sow., Am. Henleyi, Sow. 



4. — The zone of Ammonites margaritatus forms an important 

 sub-division of the Lias formation; the Marlstone and Iron- 

 stone series of Yorkshire, and the Marlstone of the Midland 

 Counties, being comprised in this and the following zone. In 

 Gloucestershire the lower portion of the Marlstone consists of a 

 series of yellowish, grey, and brown Sands, with thin bands 

 of calcareous Limestone and ferruginous nodules; the upper of a 



