MITCHELL — GLYPTOLEPIS IN THE SANDSTONE OF DURA DEN. 43 



afforded. In the meanwhile, without prejudging the question 

 whether the fossil before us be referable to a freshwater or a marine 

 form, I incline slightly to the former opinion." 



Remains of scutes of Chelonian reptiles have, since this specimen 

 has been in our hands, been offered for purchase to the officers of the 

 British Museum ; but whether they belong to the same species we 

 are not in a position at present to hazard an opinion. 



We may add that M. Hugi has discovered in the Kimmeridian 

 beds of Soleure bones of Emys, associated with marine mollusca. 

 Pictet suggests that their remains may have been transported by 

 freshwater currents. 



As a provisional arrangement, we would prefer to include our 

 specimen in the genus Chelys, giving it a characterizing specific 

 name in honour of our friend who has so obligingly worked out its 

 relationship to the other reptiles of the interesting family to which 

 it belongs. 



ON THE OCCURRENCE OF GLYPTOLEPIS IN THE 

 SANDSTONE OF DURA DEN. 



By tue Rev. Hugh Mitchell, M.A. 



In his admirable essay on the Devonian Fishes, in the Tenth De- 

 cade of the Geological Survey, Professor Huxley has clearly indicated 

 and described the differences and the resemblances of the genera 

 Holoptychius and Glyptolepis. In the interesting work of the Rev. 

 Dr. Anderson on ' Dura Den,' in which its exquisitely-preserved 

 ila are described, do mention is made of Glyptolepis. In the 

 November part of the 'Journal of the Geological Society of London,' 

 J\l r. Powrie lias called attention to the occurrence of Glyptolepis in 

 slabs recently disinterred, for the St. Andrew's Museum, from Dura 

 Den. Through the kindness of Dr. Anderson, a slab was presented 

 to the Montrose Museum in 1859 ; and it is now apparent from it 

 that Glyptolepis is not of rare occurrence at Dura Den, and that 

 either this genus has been passed over altogether, or confounded 

 with Holoptychius. The fishes in the Montrose Museum are smaller, 

 and do not in all points correspond with those described by Mr. 

 Powrie, but we think they emphatically demonstrate that the Holo* 

 ptychius Flemiiiyii must now be denominated Glyptolepis. 



On the slab in the Montrose Museum there is one line specimen 

 of Holoptychius and six specimens of Glyptolepis, not regarding 

 fragmentary portions of fishes. At the first glance there is a resem- 

 blance in size, in general aspect, and outline, among the fishes. 

 Their average length is about nine inches, and their breadth at the 

 thickest part of the body nearly three inches. But, on looking more 

 closely, we at once discover the characteristic differences of the 



