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COTTESWOLD,

 MIDFOKD, 
 AND 
 YEOVIL 
 SANDS, 
 ETC. 
 457 
 

On

 the 
 other 
 hand 
 the 
 " 
 Midford 
 Sands 
 " 
 have 
 been 
 defined 
 as 
 

equal

 to 
 the 
 zones 
 of 
 Amm. 
 ojpalinus 
 and 
 Amm. 
 jurensis 
 * 
 ; 
 but, 
 

in

 all 
 probability, 
 the 
 lower 
 part 
 of 
 the 
 Cotteswold 
 Sands 
 — 
 the 
 part 
 

containing

 Amm. 
 bifrons 
 — 
 belongs 
 to 
 the 
 Commune-zone. 
 Then, 
 too, 
 

it

 is 
 just 
 the 
 opposite 
 in 
 Somerset, 
 where 
 it 
 is 
 the 
 Upper-Lias 
 Clay 
 

of

 Ilminster 
 which 
 contains 
 the 
 greater 
 part 
 of 
 the 
 Jurense-zone. 
 

Again,

 part 
 of 
 the 
 Inferior-Oolite 
 Limestone 
 of 
 Dorset 
 and 
 of 
 the 
 

Cotteswolds

 is 
 in 
 the 
 zone 
 of 
 Amm. 
 opalinus. 
 Therefore 
 this 
 latter 
 

definition

 does 
 not 
 coincide 
 with 
 the 
 first. 
 

According

 to 
 either 
 view 
 we 
 arrive 
 at 
 an 
 absurdity, 
 namely, 
 part 
 

of

 the 
 Upper-Lias 
 Clay 
 must 
 be 
 in 
 the 
 Inferior 
 Oolite 
 series 
 ; 
 or 
 

beds

 containing 
 several 
 of 
 the 
 same 
 species 
 of 
 Ammonites 
 must 
 be 
 

in

 the 
 Lias 
 in 
 one 
 place, 
 and 
 in 
 the 
 Inferior 
 Oolite 
 in 
 another. 
 

After

 all, 
 the 
 term 
 " 
 Midford 
 Sands 
 " 
 is 
 only 
 used 
 locally. 
 The 
 

Dogger

 Sands 
 of 
 Yorkshire, 
 and 
 part 
 of 
 the 
 Northampton 
 Sands, 
 

are

 contemporaneous 
 with 
 the 
 upper 
 part 
 of 
 the 
 Yeovil 
 Sands 
 ; 
 but 
 

they

 are 
 not 
 included 
 in 
 the 
 term 
 " 
 Midford 
 Sands." 
 Is 
 there 
 the 
 

least

 advantage 
 in 
 retaining 
 a 
 term 
 — 
 a 
 merely 
 local 
 term 
 — 
 which, 
 as 
 

I

 have 
 shown, 
 includes 
 deposits 
 that 
 are, 
 by 
 no 
 means, 
 contempor- 
 

aneous?

 Its 
 only 
 advantage 
 is 
 that 
 it 
 does 
 away 
 with 
 two 
 names; 
 

but

 the 
 result 
 is 
 absolute 
 inaccuracy. 
 The 
 terms 
 Cotteswold, 
 Mid- 
 

ford,

 and 
 Yeovil 
 Sands 
 may 
 be 
 retained 
 as 
 merely 
 local 
 names 
 for 
 

certain

 deposits, 
 in 
 the 
 same 
 way 
 as 
 Pea-grit, 
 Oolite 
 Marl, 
 &c. 
 ; 
 

they

 should 
 have 
 no 
 wider 
 signification 
 than 
 the 
 district 
 to 
 which 
 

they

 apply, 
 and 
 should 
 not 
 be 
 used 
 where 
 strict 
 scientific 
 accuracy 
 

is

 required, 
 but 
 should 
 give 
 place 
 to 
 their 
 zonal 
 equivalents. 
 

It

 would 
 almost 
 seem 
 as 
 if 
 the 
 sands 
 between 
 Liassic 
 Clay 
 and 
 

Oolitic

 Limestone 
 were 
 a 
 somewhat 
 singular 
 deposit 
 ; 
 but 
 the 
 fact 
 

of

 the 
 matter 
 is, 
 that 
 from 
 a 
 rather 
 remote 
 period 
 until 
 a 
 much 
 

later

 one 
 than 
 we 
 are 
 treating 
 of, 
 sandy 
 strata 
 have 
 been 
 deposited 
 — 
 

in

 no 
 two 
 districts 
 contemporaneously, 
 but 
 generally 
 first 
 in 
 one 
 

place

 and 
 then 
 in 
 another. 
 Why, 
 then, 
 is 
 it 
 desired 
 to 
 mark 
 off 
 the 
 

"

 Midford 
 Sands 
 " 
 as 
 a 
 distinct 
 series 
 — 
 not 
 all 
 across 
 England, 
 but 
 

only

 locally 
 ? 
 

The

 Jamesoni- 
 and 
 Caprleornum- 
 zones 
 are 
 characterized 
 by 
 mica- 
 

ceous

 and 
 sandy 
 shales 
 at 
 Eobin 
 Hood's 
 Bay 
 in 
 Yorkshire 
 t. 
 

The

 Henley 
 i-zone 
 in 
 Gloucestershire 
 is 
 largely 
 made 
 up 
 of 
 sandy 
 

strata

 very 
 similar 
 to 
 the 
 Cotteswold 
 Sands. 
 

The

 Margaritatus- 
 and 
 Spinatus-zones 
 in 
 Dorset 
 contain 
 sandy 
 

strata

 often 
 undistingnishable 
 from 
 the 
 Yeovil 
 Sands. 
 

The

 zone 
 of 
 Amm. 
 annulatus 
 in 
 Yorkshire 
 is 
 represented 
 by 
 hard 
 

and

 compact, 
 grey 
 and 
 micaceous 
 sandy 
 shale 
 t. 
 

What

 is 
 probably 
 the 
 upper 
 part 
 of 
 the 
 Commune-zone 
 is 
 com- 
 

posed

 of 
 micaceous 
 sands 
 in 
 Gloucestershire. 
 

The

 Jurense-zone 
 is 
 made 
 up 
 of 
 sands 
 at 
 Bath, 
 while, 
 lastly, 
 the 
 

OpaUnum-zone

 at 
 Burton 
 Bradstock 
 is 
 chiefly 
 sands. 
 

Passing

 to 
 the 
 continent, 
 Oppel 
 § 
 shows 
 us 
 that 
 at 
 Wasseralfingen 
 

 H. 
 B. 
 Woodward, 
 op. 
 cit. 
 p. 
 285. 
 

f

 H. 
 B. 
 Woodward, 
 op. 
 cit. 
 p. 
 269.