822 REPORT—1890. 
The author concludes that either there isa considerable body of underground water 
at some intermediate spot between the water-sink and the cove, or that the Aire- 
head spring communicates.with some water-sink—possibly the one he had noticed— 
other than that marked on the Ordnance Survey maps. 
7. Report on the Collection, Preservation, and Systematic Registration of 
Photographs of Geological Interest.—See Reports, p. 428. 
8. Onthe Discovery of a Jurassic Fish-Fauna in the Hawkesbury-Wianamatta 
Beds of New South Wales. By A. Su1ra Woopwarp, I’.G.S. 
A large collection of fossil fishes from the Hawkesbury-Wianamatta series of 
Talbralgar, New South Wales, has been forwarded to the author for examination 
by Messrs. C. S. Wilkinson and R. Etheridge, jun., of the Geological Survey of 
New South Wales. The final results will appear in a forthcoming memoir, to 
be published by that Survey ; but the investigation has already proceeded so far as 
to justify the announcement of the discovery of a typically Jurassic fish-fauna in 
Australia. Fine examples of the Paleoniscid genus Coccolepis occur, and this 
has previously been met with only in the Lower Lias of Dorset, the Purbeck beds 
of Wilts, and the lithographic stone of Bavaria. A new fish, allied to Semzonotus, 
but with thinner, much imbricating scales, is also conspicuous; and another new 
form, allied to the Dapedioids, is remarkable from the presence of typical 
rhombic ganoid scales in the front half of the trunk and deeply-overlapping cycloid 
scales over the whole of the caudal region. A Leptolepis-like fish, with a persistent 
notochord, seems to represent a third unknown generic type. Of Leptolepis itself 
there are many hundreds of individuals in a fine state of preservation. The 
fishes occur in a hard, ferruginous, fissile matrix, associated with well-preserv ed 
remains of plants. 
9. Restorations of the Paleozoic Elasmobranch Genera Pleuracanthus and 
Xenacanthus. By Dr. Axron Frirscu. (Communicated by A. Sire 
Woopwarp.) 
The author forwarded for exhibition the series of plates illustrating the forth- 
coming part of his work on the fauna of the Lower Permian gas coal of Bohemia. 
These were devoted to Plewracanthus and Xenacanthus, of which the examination 
of more than 200 specimens had enabled the author to attempt nearly complete 
restorations. The chief result of the investigation is that the three genera, Ortha- 
canthus, Pleuracanthus, and Xenacanthus, are well characterised, and prove to be 
true Selachians, having the cranial cartilage simple, with no distinct tracts of ossi- 
fication. The skull resembles that of Hybodus and the Opistharthri of Gill. There 
are seven branchial arches, as in Heptanchus. The median fins are embryonic in 
character, and the two anal (?) fins take the place of the lower part of the hetero- 
cercal caudal tin. The pectoral fin is most primitive in Orthacanthus, more 
advanced in Xenacanthus, and still more resembling that of recent sharks in 
Pleuracanthus, There is no pelvic arch. The claspers of the male closely resemble 
those of recent Elasmobranchs, and are formed by modified postaxial rays. Inter- 
calaria are developed in the vertebral column, but the notochord is persistent. 
10. On Fossil Fish of the West Riding Coal-field. 
By J. W. Davis, F.G.S. 
The first recorded discovery of fossil fish-remains in the West Riding was in 1833, 
when Professor Johnston of Durham, along with a number of local geologists, found 
the remains of a large fish in the Deep coal at Middleton (which afterwards served 
as the type of the genus Megalichthys when the late Professor Agassiz visited Leeds 
