PALEONTOLOGY 



In addition to the foregoing specimens mention must also be made 

 of a fine plesiosaurian skull from the Lower Lias of Cropwell Bishop 

 recently acquired by the Nottingham University College Museum. 

 The generic and specific determination of this specimen does not hitherto 

 appear to have been attempted. It is stated in Mr. W. J. Harrison's 

 Geology of the Counties of ILngland 1 that remains of plesiosaurs together 

 with those of ichthyosaurs another group of marine reptiles confined 

 to the Secondary period occur plentifully in the Lower Lias near 

 Cortlingstock. 



From the Rhaetic deposits of the county have been obtained, 

 according to Prof. Carr, presumed reptilian coprolites, which may belong 

 to one or both of the aforesaid groups. 



Footprints of amphibians are rare in the Keuper formation of the 

 county, but one example from the foot of the railway cutting at Colwick 

 is now in the possession of the Nottingham High School. There is 

 also a statement 1 to the effect that amphibian footprints, of the type 

 known as Chirosaurus or Cbirotberium^ have been observed in the Keuper 

 sandstone of Weston ClifF, on the Nottinghamshire side of the Trent. 

 And Mr. Harrison 3 likewise states that similar footprints have been 

 met with in the Keuper south of Ollerton. Such footprints, it may be 

 well to mention, were probably made by gigantic primeval salamanders 

 or labyrinthodonts, allied to or identical with Mastodonsaurus. Foot- 

 prints of the same nature likewise occur in the Permian Magnesian 

 Limestone at Mansfield, and there is a fine slab displaying a number of 

 such impressions in the Nottingham University College Museum. 



Fish remains appear to be very scarce in the Secondary formations 

 of the county, but from the Rhstic Prof. Carr records, bones, teeth and 

 fin spines assigned to the genera Hybodus, Nemacantbus, Acrodus, Gyro/epis, 

 Saurichthys and Ceratodus. 



Of much greater interest however are numerous remains of the 

 ganoid or enamel-scaled fish known as Semionotus brodiei^ which occurs 

 typically in the Keuper of Warwickshire. The Nottinghamshire speci- 

 mens were discovered in 1879 by Mr. E. Wilson* in the roof of a 

 tunnel which was at that time being driven through the so-called ' water- 

 stones ' of the Upper Keuper at Colwick Wood near Nottingham for 

 the Lean valley outfall sewer. In recording this ' find ' Mr. Wilson 

 makes the following observations : 



In addition to the exceptional interest that is always to be derived from the pre- 

 sence of organic remains in Triassic rocks, as a rule so barren of life, there were two 

 points specially noticeable in connection with the occurrence of these fossils in the 

 Keuper at Nottingham ; namely, first, the great number of the fishes, there being 

 quite a shoal of them for a distance of 30 feet or thereabouts in the line of section, 

 the individual fishes even lying over one another in the middle portion of that distance, 

 but gradually becoming more widely separated in either direction until they finally 

 came to an end ; and, secondly, their occurrence at the junction of two formations of 

 the Trias, namely, of the waterstones of the Upper Keuper and the basement beds 

 (Lower Keuper). 



1 p. 211. 2 See Hall, Mem. Geol. Survey United Kingdom (1860). 3 Op. cit. 



* See Quart. Journ. Geol. Sac. xliii. 542 (1887). 



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