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abundance. In fact from the numbers of this Conchifera they may 

 well be called the Lima prcecursor beds. As these beds graduate 

 upwards into the more solid beds of the true White Lias, life 

 becomes less abundant, and, with the exception of a much weathered 

 coral or two (Montlivaltia) and a solitary cast of a shell, probably 

 Lima inversa, Terq., which occuiTed in one of the top beds at the 

 N.W. end of the cutting, no single trace of an organism has been 

 found. There is nothing particularly remarkable in these seven or 

 eight cream coloured solid beds, 6 feet in thickness, with their 

 filmy partings of yellow clay, except their great development in this 

 section,which renders it, perhaps, the typical section of the W. for 

 the junction of the White and Lower Lias. Immediately overlying 

 the " Sun bed " of William Smith (No. 19) occurs a thin band of 

 yellowish-brown arenaceous shale (No. 20). As this band invariably 

 lies on the top of the White Lias throughout the section I have 

 made it the datum line whence to make my measurements. It 

 varies but little in thickness (2 inches), and contains Ostrea liassica, 

 Modiola, and fish scales, and is the first representative of the Ostrea 

 beds of the Lower Lias at Garden Cliff and elsewhere. This 

 arenaceous band shows that a great change had taken place since 

 the Rluetic waters had left their calcareous deposits, represented 

 by the thick beds of the White Lias so destitute of organisms, and 

 ushers in again a period when life became more abundant until it 

 culminated in the richly fossiliferous zones of Molluscan and Saurian 

 life in the Lias above. With this band commences, then, the beds 

 of the succeeding Lower Lias. The Insect and Crustacean beds of 

 Camel, about 5 feet in thickness, are here apparently wanting, and 

 the Ostrea and Ammonites angulatus zones immediately succeed the 

 White Lias. The change from the creamy colour of the lower 

 beds to the reddish-brown ferruginous beds, marked 21 to 36, is 

 very conspicuous. Some of the limestone bands are very fos- 

 siliferous, and contain Ostrea liassica, Myacites, Astarte, Cardinia, 

 Trochus angulatus, Turritella, Ammonites angulatus, &c. The lower- 

 most beds are very close, compact, and somewhat siliceous, the 

 fossils appearing in casts with carbonate of lime crystals adhering. 

 These beds are divided by bands of reddish-brown arenaceous 

 marl, and have small weathered A mmonites and Gasteropoda on their 



