260 [Proc. B.N.F.C, 



These Chalk beds repose on the worn surface of the Upper Green- 

 sand, to which the beds numbered 4.a., 4.b., 4.C., 5, and 6 belong. 

 These last-mentioned beds are the representatives of the Upper 

 Greensand beds of Blackdown, and other parts of England, being 

 our oldest Cretaceous strata, and belong to the Cenomanien divi- 

 sion of French geologists. Beds Nos. 4-a., 4.b., and 4.C thin out 

 to the north-east end, and are limited in this direction by a fault 

 south-west of Crow Glen. In the section at this latter place they 

 are not seen, rocks belonging to bed No. 3 resting on the eroded 

 surface of No. 5 ; nor are they seen again in any of the sections 

 to the north-east, as far as Woodburn and Islandmagee; their 

 place being taken by a bed of bluish-coloured calcareous grit, 

 with large grains of quartz and glauconite, the fossils of which 

 prove its affinity to the beds below the lower chalk of England, 

 called the chalk marls of the Turonien division of the French 

 geologists. That this is the true position of the Woodburn beds, 

 the reader stated that he had no doubt, whatever ; lithological and 

 palaeontological evidence prove it to be so, and the discovery by 

 him of Terebratulina gracilis in the Woodburn bed is a further 

 proof of this statement. This very characteristic fossil has not 

 been found in any other bed in this locality. Spondylus spinosus 

 is also a Chalk fossil, and proves that the beds containing it have 

 no claim to be considered as true members of the Upper Green- 

 sand division of the Cretaceous formation. The following 

 table gives the classification of our Irish Cretaceous strata by the 

 geologists who have written on the subject, for comparison with 

 the correlation here adopted : — 



