392 Microscopical Society, 



though a specific identification with the analogous fossils of the 

 German keuper has not been ascertained. The only instances on 

 record of muschelkalk fishes found in Great Britain, are scales from 

 the Bone Bed at Aust Cliff, and referred by Professor Agassiz to 

 Gyrolepis Albertii and G. tenuistriaius, common continental muschel- 

 kalk fishes. This bed it is well known occurs at the base of the lias, 

 and rests conformably on the green and red marls of the new red 

 sandstone. A thin stratum replete with remains of saurians and 

 ichthyolites occupies a similar stratigraphical position near Axmouth ; 

 and Prof. Agassiz, during his visit to England in the autumn of 1840, 

 identified in a series of specimens obtained by Miss Mary Anning, 

 one Placoid, two Lepidoid, and one Sauroid fish, with well-known 

 muschelkalk species. He also determined the existence of fifteen other 

 species from this deposit, none of which have been yet noticed in 

 the continental Triassic group. Two, if not three, of the above 

 muschelkalk ichthyolites are also found at Aust ; and a comparison 

 of the Aust and Axmouth species gives five as common to the two 

 localities, twelve as confined to the former, and two to the latter. 

 The only conclusion, Sir Philip Egerton states, which he feels justi- 

 fied in advancing from the facts adduced in this communication is, 

 that the beds in question, hitherto considered as belonging to the 

 lias, must be removed from that formation, inasmuch as they pre- 

 sent a series of fishes not only specifically distinct from those of 

 the lias, but possess in the Ganoid genera the heterocerqjie tail, 

 an organism confined to the fishes which existed anterior to the lias. 

 Appended to the paper is a systematic catalogue, compiled from 

 the ' Poissons Fossiles/ of the Ichthyolites hitherto described, from 

 the keuper and muschelkalk of the Continent, together with those 

 recently discovered at the Aust Passage and near Axmouth. The 

 following extract from that document contains the species common 

 to the Continent and England ; — 



Continental Localities 

 Order. Genus and Species. English Localities. and Formations. 



Placoid. Hybodus plicatilis. Axmouth. Passim. Muschelkalk. 



Ganoid. Gyrotepis Albertii. Ibid.— Aust. Passim. Ibid. 



,, tenuistriatus. Ibid. — Ibid. Passim. Ibid. 



„ Saurichthys apicalis. Ibid. Bayreuth. Ibid. 



MICROSCOPICAL SOCIETY OF LONDON. 



At a meeting of the Microscopical Society, held November 24th, 

 N. B. Ward, Esq., in the Chair, a paper was read from the Rev. 

 J. B. Reade, entitled, " A Postscript to the Rev. J. B. Reade's paper 

 on the Process of Charring Vegetable Tissue as applied to the Sto- 

 mata in the Epidermis of Garden Rhubarb ;" in which the author, 

 after alluding to the experiments of Dr. Williams, as communicated 

 to the Society in August last, which appeared to lead to the conclu- 

 sion, that the process of charring was of very doubtful efficacy in de- 

 termining delicate structure, suggests that the overlying membrane 

 in stomata was really nothing more than an inspissation of gelatinous 

 mucus raised by heat into contact with the glass, and by the pressure 



