406 PEOCEEDINGS OF THE GEOLOGICAL SOCIETT. [May 10, 



I append a list of the organic remains from the " Nubian Sand- 

 stone " series : — 



! Orthis Michelini Wady-Nasb Limestone. 



! Streptorhynchus crenistria 

 ! Spirifera (fragments of) 



* Murchisonia 



* Eulima? 



* Ehodocrinus 



!* Poteriocrinus 



* Lepidodendron Mosaicum . Wady-Nasb Sandstone. 

 ! Sigillaria, sp. „ „ 



[The sign ! prefixed to the names of the fossils indicates that the 

 specimens were collected by the Sinai Survey ; and the sign * in- 

 dicates the determination of Mr. Salter.] 



In conclusion I venture to suggest that the Adigrat Sandstone in 

 Abyssinia, described and so named by Mr. "W. T. Blanfordf, is of 

 the same age as the Nubian Sandstone. It appears to have escaped 

 the notice of that author that the Sandstone of Adigrat is similar in 

 character and general appearance to the Nubian Sandstone, and 

 that it, moreover, overlies the schistose rocks in the same manner, 

 and contains iron-ore and psilomelane, as in Sinai. Mr. Blanford 

 surmises, however, that " both the coal-bearing beds of Chelga and 

 the Adigrat Sandstone may belong to a portion of the great series 

 associated with [Triassie] coal in India " {loe. cif. p. 175) ; but the 

 Talcheer and other coals are referred by Messrs. Blanford and Theo- 

 bald- to a Permian age (Mem. Geol. Surv. India, vol. i.). 



Note. — My attention has been called since the reading of this 

 paper to Prof. Unger's observations on the Fossil Wood from Assuan 

 and Um-Ombos, in the Nile vaUey (Quart. Journ. Geol. Soc. vol. xv. 

 Misc. p. 13, 1859). The wood belongs to. a coniferous tree of the 

 Araucarian division, and is named Dadoxylon cegyptiacum ; its 

 habitat is assumed "to be the sandstone, which occurs extensively 

 in Upper Egypt and Nubia, between the granite and Cretaceous 

 beds," in which case Dadoxylon cegyptiacum was contemporaneous 

 with Lepidodendron mosaicum, and Sigillaria. Prof. Unger argues, 

 from the presence of this genus, that the sandstone, " hitherto of 

 doubtful rank in the geological series, as no organic remains have 

 been found in it," should be ranked in the Permian, rather than in 

 the Keiiper or the Cretaceous formation ; but from the palseonto- 

 logical evidence alone he might have argued equally in favour of 

 its Carboniferous age. 



3. On the Discovert of the Glutxojst (Gitlo Luscrs) in Britain. 

 By W. Boyd Dawkus^s, Esq., M.A., F.R.S., F.G.S. 



The caves in the Mountain Limestone which forms the magnificent 

 gorge of the Elwy, near Cefn, St. Asaph, have furnished from time 



t Greology and Zool. of Abyssinia, p. 170. 



