1927 CHRONOLOGY 51 



the result of some twenty years' collecting by various people — local 

 residents. It is a pity the specimens are so rare, for the ammonoid 

 fauna yielded by Troll quarry is almost, if not quite, unique in England. 



The last paragraph was written prior to a visit in 1927. Then 

 I found a body-chamber fragment (S.B. 4751) of Tulophorites aff. 

 prcBclarus (T.A. CCCLXVIII) about the middle of the west face of the 

 quarrj' at the top of the section, close under the soil. My eldest son, 

 who accompanied me, picked up, loose, lying on a bed about the middle 

 of the section, a body-chamber fragment (S.B. 4745) of an Oppelid, 

 somewhat suggesting Ammonites serrigerus ; de Grossouvre (Bathonian ; 

 Bull. Soc. Geol. France, (3) xvi, 1888, in, 3). Its matrix is a sandy 

 marl, light straw-coloured, darker where it has been weathered. It may 

 possibly have come from bed 3 or 4. Its preservation is poor, but it 

 is valuable as being a new find for the beds of Troll, or even for any 

 English Great Oolite strata. 



With regard to the highest bed of the Troll section, this seems to 

 thicken southwards, where the quarry is grass-grown, and there appear 

 to be traces of a clay above it. 



ZiGZAGiCERATAN. On the way by road to the Troll quarry, at 

 the south-west corner of Clifton Road, where it branches off from the 

 Bradford Abbas- Yetminster road (Clifton Maybank parish), about 

 one furlong south of Bradford Abbas Vicarage, a small road-widening 

 showed yellowish stone-beds with a Zigzagicerate (S.B. 4746). There 

 is reason to suppose, owing to dip of strata and that Hke beds are not 

 shown in the Bradford Abbas quarries, that these roadside beds are 

 higher than those of the Vicarage Quarry, Bradford (Q.J.G.S., xlix, 1893, 

 p. 486, § III). Therefore the reason why the Zigzagicerate fauna, so 

 characteristic for the top beds of Inferior OoHte of Crewkeme Station, 

 Somerset, Broad Windsor and Bridport, Dorset, had so very rarely 

 been obtained from Bradford, was that the true bed of Zigzagicerates 

 failed in exposure at any of the Bradford quarries : they were all too low. 

 It is necessary to cross the river into Clifton Maybank parish to strike 

 them. 



The Clifton-Road beds are to be dated as Zigzagiceratan, pollubnim. 

 Therefore the Bradford " top beds " are presumably ^xe-pollubrum, 

 not fusca. The Clifton beds are about a mile north of Troll quarry, 

 and some 20 feet lower, according to ground level, with something more 

 to be added for dip. What the intervening beds are like may be gathered 

 from a faulted piece of " Fullers' Earth " on the west end of the cutting 

 of the Southern Railway, east of Bradford, and from beds of Lenthay 

 Common about two mUes to the east. 



Acknowledgment 



To the subscribers for their continued kind support and to those 

 who have helped this work by contributions of MS. or illustrations, 

 by loans of specimens, books etc., by giving facilities for study, and 

 in numerous other ways, the author desires to express his heartfelt 

 thanks. 



