40 Reports and Proceedings — Royal Microscopical Society. 



to the locality from which it was derived. It appears to be an Upper 

 Corallian form, and is usually taken as the zone-fossil of that horizon. 

 Sowerby's two figures of Perisphinctes btplex represent different 

 specimens, one of which is dismissed from consideration. The other, 

 probably from a Kimmeridge Clay nodule found in the Suffolk Drift, 

 is refigured and described. The authoress considers that it would 

 be wisest to abandon the name altogether, or at least to restrict it to 

 the abnormal specimen to which it was first attached. The original 

 specimen of Ferisphinctes variocostatus (Buckland) came from the 

 so-called Oxford Clay at Hawnes, 4 miles south of Bedford ; but the 

 authoress gives evidence in favour of her belief that it was really 

 derived from the Ampthill Clay. Sowerby's Ammonites i-otundus is 

 the last species figured, and it is doubtfully identified as a variety of 

 Olcostephaniis Pallasianus (D'Orb.). It was derived from the 

 Kimmeridge Clay of Chippinghurst, 6^ miles south of Oxford, and 

 is the zone-fossil of the Upper Kimmeridge Clay. 



2. " On the occurrence oiJSdestus in the Coal-measures of Britain." 

 By Edwin Tulley Newton, Esq., F.R.S., V.P.G.S.^ 



This genus was originally described from the United States, and 

 was afterwards recognized in beds of similar age in Russia and 

 Australia. The genus was afterwards placed with Belicoprion and 

 Campyloprion in the family Edestidse. The specimen described in 

 the present paper was obtained by Mr. J. Pringle from one of the 

 marine bands which occurs between the ' Twist Coal ' and the 

 ' Gin Mine Coal,' in the Smallthorn sinking of Messrs. Robert 

 Heath & Son's pits at Nettlebank (North Stafi'ordshire). Several 

 other marine bands, chiefly met with during the sinking of shafts in 

 this coalfield, have been studied by Mr. J. T. Stobbs, who called the 

 attention of the Geological Survey to the exposure from which this 

 specimen was obtained. The specimen is a single segment of a 

 fossil very closely resembling Edestus minor, and consists of an 

 elongated basal portion, bearing at one extremity a smoothed, 

 enamelled, and serrated crown. A description of the fossil shows 

 that it is not to be referred to any existing species, and a new name 

 is given to it. While it seems most in accordance with present 

 knowledge to regard the ' spiral saw ' of Melicoprion as the enrolled, 

 symphysial dentition of an Elasmobranch, possibly allied to the 

 Cestracionts, it does not seem nearly so probable that the forms 

 referred to Edestus are of the same nature. In the opinion of the 

 author the latter are more likely to be dorsal defences. The paper 

 concludes with a bibliography of the subject. 



11. — Royal Microscopical Society. 



At the ordinary meeting on December 16th, 1903, Dr. Henry 

 Woodward, F.R.S., President, in the chair, the following paper 

 was read : — 



' Comiuuuicated by permission of the Director of H.M. Geological Survey. 



