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 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. i 25 4