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ever, to the geologist that this district has most attractions, as 

 there are few localities to be found where a series of rocks so 

 varied as those seen in Colin Glen are displayed in so small a 

 compass. Commencing at the lower part of the glen, the geolo- 

 gical student may investigate strata of Triassic age, consisting of 

 the variegated marls known as the Keuper formation. These are 

 of very great thickness, and, as usual elsewhere, entirely devoid of 

 fossils. Passing upwards, the strata next in order are the highly 

 interesting " Avicula contorta beds," which are more extensively 

 developed in Antrim than anywhere else in Britain. These beds 

 consist of soft friable shales, with thin courses of impure limestone, 

 and are highly fossiliferous. There are also several very thin 

 sandy bands, which are charged with the remains of fish and 

 reptiles, mainly the teeth and scales. Owing to a great mass of 

 stones having fallen from the bank above, and covered up the 

 section where these " bone beds " were best displayed, no speci- 

 mens of Rhaetic fish or reptilian remains were obtained on this 

 occasion. Next in order above the Rhaetic beds, and occurring 

 both below and above the bridges crossing the glen, are found 

 shales and limestones belonging to the Lower Lias proper. The 

 sections are not, however, the most interesting or instructive that 

 may be found in the county. The series are not well displayed, 

 and consist of the very lowest members of the Lower Lias — known 

 as the " Ammonites planorbis zone" — a zone that contains but few 

 fossils, and these not in good preservation. The more fossiliferous 

 portions of the Lias are only slightly exposed in Colin Glen. 

 Superimposed on the Lias there occur considerable masses of 

 rocks belonging to the Upper Greensand. This formation is 

 largely developed here, and consists of soft, dark green sands 

 (Glauconitic sands), yellow cherty sandstones, and light green 

 sands and sandstones ; the whole series being estimated by Pro- 

 fessor Ralph Tate, F.G.S., at 54 feet in thickness, though appear- 

 ing to be much more, owing to repetitions of the same beds in 

 the stream, in consquence of vast rock slips which have occurred 



