Grange. — Geology of Green Island Coalfield. 163 



The lower 20 ft. of Loudon's pit is composed of alternating bands of 

 coarse and fine sand ; above rests a coarse sand with pebbles up to 1 in. 

 diameter, followed by a cemented band 1 in. thick, which in turn is over- 

 lain by a layer of fine material. 



The old sand-pit near the Southern Trunk Railway consists of bands 

 of coarse and fine sand alternating in a regular manner. 



The Jubilee sand-pit has a bed of white well-rounded sand. A layer 

 of gravel forms the uppermost portion of this deposit at Brighton. 



Shelly Limestone. 



This formation outcrops in vertical cliffs in the valley above Brighton 

 Creamery, where it has a thickness of 50 ft., but no outcrop of the lime- 

 stone was found at any other locality. 



McKay (1877, pp.* 59-60) in his report for 1873 says that his Green 

 Island fossils were obtained from a concretionary greensand. 



The collection contains, besides fossils from the greensand, pieces of 

 shelly limestone similar to that occurring at Brighton. The shaft to which 

 the collector refers was in all probability Clarkson's, which was situated 

 from 10 to 15 chains east of Walton Park Colliery. 



The limestone, which is the only bed giving an indication of the age 

 of the series, has yielded few good specimens. The following have been 

 obtained : Pecten n. sp., Belemnites sp., Ostrea sp., Venericardia sp. 



The Pecten the writer obtained has a strong midrib, and is unlike any 

 New Zealand species hitherto described. The bad state of preservation 

 of the Belemnites makes its determination difficult. Hector (1874, p. 356), 

 taking as his holotype the dibranchiate cephalopod from the greensand 

 of Amuri Bluff, described the form in the Brighton and Amuri beds as 

 Belemnitella lindsayi, but in his Progress Reports of 1873-74 ([>. xii) expressed 

 the opinion that the fusiform bodies were, true Belemnites, and termed them 

 Belemnites lindsayi. Later (1887, p. xxix) he again identified the Brighton 

 fossil as a Belemnitella. Park (1910b, p. 90) sent specimens to Dr. Bather, 

 who pronounced them to be true Belemnites. Marshall (1917, pp. 459-60) 

 sent them to authorities on Belemnites. Professor Stolley, of Brunswick, 

 stated they belong to Hibolites ; Professor Steinmann, of Bonn, and Pro- 

 fessor Holzapfel, of Strassburg. regarded them as similar to Belemnites 

 minimus of the Chalk ; and Lissajous reported that they belong to the 

 genus Neohibolites Stolley. The ages given by these authorities range 

 from Upper Jurassic to Cretaceous. The determinations make the fossil a 

 belemnite or a subgenus of Belemnites that does not reach the Eocene. 

 Trechmann (1917, pp. 338-39) compares the Brighton form with the 

 belemnites in the Upper Senonian of Selwyn Rapids. 



Tentatively the shelly limestone and the coal-measures that underlie it 

 may be placed in the Piripauan. 



By Park (1910b, pp. 90, 112) and Hutton and Ulridi (1875, pp. 46-48) 

 the coal-measures of Green Island and Abbotsford were thought to be 

 Tertiary in age. The first-named writer placed the Brighton coals in the 

 Cretaceous, but Hutton (1885, p. 266), considering the identification of the 

 fusiform bodies of the shelly limestone doubtful, uses other palaeontological 

 evidence and finds no Cretaceous rocks in the area. 



Marshall (1906, p. 389) gives a Tertiary age to all the coal-measures of 

 the Green Island coalfield, on the ground that the cephalopod is Actinocamax, 

 but later (1916, pp. 117-19) accepted Hector's determination, Belemnites 

 lindsayi, and correlated the Brighton beds with the Wangaloa beds. 



