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but at Lyme, in Dorsetshire, they abound, and range from the middle to the 

 lower inclusive, and the same may be said of the saurians, which are not 

 limited there to the insect and saurian beds, still lower in the series, though 

 they are for the most pait in Gloucestershire, "Warwickshire, and Leicester- 

 shire. In many places these clays are extensively used for brick making, for 

 though they contain concretions here and there, there are no bands of solid 

 limestone amongst them. Below them, however, thick and valuable beds of 

 limestone largely prevail, and are often quarried for lime, walla, and roads ; 

 they make a very bad material for this latter purpose. The uppermost of 

 this more calcareous portion of the Lias has received the designation of 

 " Lima beds," from the abundance of a large livui, the I. gifjantea, which 

 has a very wide horizontal range, for in various parts of England, where I 

 have examined this division of the Lias, I have always met with specimens 

 of this fine shelL The two finest inland sections of this division with which 

 I am acquainted are at Frethern Cliff, in Gloucestershire, and Saltford, on 

 the Great Western Railway between Bath and Bristol, and on the same 

 line at Harbury, near Leamington, in Wariivickshire, and at my friends*, 

 Messrs. Greaves and Kirshaw's pits at Harbury and Stockton, a few miles 

 distant, where the limestones, as at Wilmcote, still lower in the series, are 

 used for making hydraulic cement. The railway cutting at Harbury presents 

 the following section, in desceading order : — Six beds of limestone, the upper- 

 most white and rubbly, divided by clay containing lima gigantca and other 

 shells; black shale, 2 ft. ; limestone, full of rhynchonella variabilis, 1 it. ; dark 

 shale, 2 ft.; blue limestone, fucoid bed; ten beds of limestone, divided by 

 shale seen in succession ; shale, 3 ft. ; thick band of hard blue limestone, one of 

 the thickest in the section, not exceeding 2 ft. ; irregular masses of limestone 

 in shale 4 ft. ; five beds of limestone in regular layers, divided by a thick 

 stratum of dark shale. Unfortunately the rest of the section is covered up by 

 debris, so that the strata cannot be observed down to the white Lias, which 

 appears at the north-western end of the cutting and rises gradually in that 

 direction, and is quarried at many places in the neighbourhood. With the 

 exception of the uppermost layers of limestone, all the rest are, as usual, of 

 a blue colour, varying in thickness from a few inches to two feet. The entire 

 thickness which could be measured en maise is from 30 to 40 feet, but if 

 the shale now concealed could be added it would much exceed this. If the 

 Insect and Saurian beds are represented in this section, they are but very feebly 

 developed. It is not always easy to correlate distant sections, even in the 

 same zone, with each other, because some beds thin out and others come in, 

 but even where the relative thickness varies, the lithological character and 

 zoological contents of the "Lima beds" 'generally throughout England are 

 very similar, and may thus be readily identified. At Saltford, according to my 

 friend Mr. Sanders, they attain a thickness of 54 feet, and at Lyme my friend 

 Dr. Wright states them to be 35 feet 4 inches. At the former place the 

 strata which intervene between them aaid the white Lias would seem to be 



