PALAEONTOLOGY 



able number of specimens. It should be added that a fish from the horizon 

 of the Kimeridge Clay known as Leptolepis sprattiformis has been recorded 

 from the Barrow Lias, but it is probable that this is a misidentification of 

 remains referable to the above-mentioned Heterolepidotus. 11 Whether another 

 species of the same genus, Leptolepis bronni (c once ntricus] , occurs at Barrow 

 seems to be open to doubt. Reverting to the family Eugnathidae (Leptolepis 

 belonging to a family of its own, which approaches the modern type of bony 

 fishes), we find that the Barrow Lias has a peculiar species (P. minor] of the 

 widely-spread Liassic genus Ptycbolepis, which takes its name from the deep 

 grooves in the enamel-coated scales. The type specimen of P. minor, now in 

 the British Museum, was described by the late Sir Philip Grey-Egerton, only 

 one other example being apparently known, and that also in the national 

 collection. This concludes the list of fishes belonging to the group Pro- 

 tospondyli from the Barrow Lias, our next representative pertaining to the 

 section Isospondyli, and to the type genus of the family Pbolidopboridae, a 

 near relation of the Leptolepididae. The Barrow species, Pbolidopborus strick- 

 landi, also occurs in the Lower Lias of Somerset. The so-called Pbolidophorus 

 egertoni, to which a brief reference is made in Mr. Browne's volume, appears 

 to have been named in error. 



Of the fishes of the Leicestershire Rhaetic perhaps the most interesting 

 is a species of lung-fish belonging to Cera fo Jus, a genus which still survives 

 in Queensland. Two of the teeth of this fish from the Rhaetic beds of the 

 Spinney Hills have been identified by Dr. Smith Woodward 18 with Ceratodus 

 latissimus, the species commonly occurring in the Rhaetic beds of Aust Cliff, 

 near Bristol. The genus takes its name from the prominent ridges on the 

 palatal teeth, which have been compared to horns ; these teeth being all that 

 was known of these remarkable fishes till the discovery of the living Australian 

 species in 1864. 



As stated by Dr. Woodward in the paper just mentioned, the crushing 

 palatal teeth of sharks belonging to the same family (Cestraciontidae) as 

 the existing Port Jackson Cestracion phllippi are occasionally met with in 

 some numbers in the Rhaetics of Wigston, some of these being assigned to 

 the widely distributed Hybodus minor, while others, it has been thought, may 

 be referable to the equally wide-ranging H. cloacinus. Not improbably the 

 fin-spines of sharks from Wigston belonging to the type known as Nema- 

 cantbus monilifer were really borne by one or other of the above-mentioned 

 species of Hybodus. Other spines and teeth from the Spinney Hills have 

 been assigned to the sharks known as Acrodus minimus and A. keuperinus. 



Remains of enamel-scaled, or ganoid, fishes appear to be rare in the 

 Rhaetic of the county, but scales of the widely-spread Gyrolepis albertii a 

 member of the family Palaeoniscidae are recorded. Other remains have 

 been assigned to Saurichthys acuminatus, a Triassic ganoid of the family 

 Belonorbyncbidae, widely distributed in north-western Europe. Sargodon 

 tomicus, a ganoid belonging to the family Semionotidae, of which remains occur 

 in the Trias of Aust Cliff and of Wiirtemberg, is also reported from the 

 Rhaetic beds of the county. Of greater interest are, however, the remains 

 of a more specialized type of ganoid fish, Pholidophorus bigginsi, otherwise 



17 Browne, op. cit. 192. 



18 Trans. Leic. Lit. and Phil. Soc. 1889, p. 29, where they are identified. 



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