406 iPROCEEBINGS OF THE GEOlOaiCAL SOCIETY. [DoC. 1, 



overlap, or are squeezed out of proportion, or are broken away, or, lastly, 

 remain buried a little way in the matrix. 



I had hoped to have completed an account of all the known fossil Estheria- 

 like Crustaceans before offering any remarks on these Caithness specimens. But, 

 for the present, I can only observe, that the form most like to them that I know 

 of is the so-called Fosidonomya Keuperiana of Germany (as far as some few casts 

 which I possess can show). Still there is a slight difference as to shape (I have 

 as yet no means of comparing the valve itself of the German triassic form re- 

 ferred to), and I prefer to regard them as distinct ; and I cannot do better than 

 dedicate this fossil Estheria of Scotland to one who has devoted so much labour 

 and time to the elucidation of its geological relations. 



Mr. Salter has lately shown me some specimens from Russia which appear to 

 be identical with Estheria Murchisoniana (but in a matrix of light-grey clay 

 very different from the Caithness flagstone). These are labelled " Asmusia mem- 

 branacea, R. Pacht;" but I do not know whether they have been described. It 

 does not appear to me at present that there are any grounds for separating these 

 fossils from the recent genus Estheria. The term membranacea, having been 

 already given to one of the Wealden Estherice {Cyclas membranacea. Sow.), is 

 preoccupied. — July, 1859. T. R. J. 



The foUowing passages respecting the fossil plants of this deposit 

 are extracted from the last edition of ' Siluria' : — 



Plants of the Caithness Flags. — The most marked addition to the fossil 

 contents of the Old Red Sandstone consists of various fossil plants. Even as 

 late as the year 1854 I could allude to only one unquestionable land-plant as 

 having been found in this formation by Hugh Miller, and described by him as 

 a part of a Coniferous tree. The same author had afterwards brought to the 

 notice of the British Association for the Advancement of Science, in 1855, 

 several of these fossil plants, which have since been published in his posthumous 

 work the ' Testimony of the Rocks.' Most of these have been there referred to 

 tree-ferns and illustrated in that work by woodcuts. 



Living at Wick, in the central portion of the Caithness flags, Mr. C. Peach 

 has laboured incessantly in that locality to discover organic remains, and has 

 succeeded in disentangling certain fossil vegetables (as well as many ichthyolites) 

 from these hard rocks. The plants are all clearly of terrestrial origin, and are 

 of the same species as those which have been found in the Orkneys by Dr. 

 Hamilton, and at Thurso by Mr. John Miller and Mr. Robert Dick, who have 

 collected many excellent specimens near that town, some of which are figured 

 below. 



[These fossil remains of vegetables have been figured and described at large in 

 the Quart. Journ. Geol. Soc. (vol. xiv. p. 72, pi. 5) by Mr. Salter, who has also 

 supplied the following succinct notes on the plants.] 



The most striking, perhaps, of these" fossil plants are very large, long, flat- 

 tened bodies, which, from their state of preservation, were clearly woody stems 

 (fig. 13. 6). They were 4 or 5 inches broad, and as many feet in length, fluted 

 longitudinally, and possessing a central pith. Though these plants have often 

 been converted into thin plates of crystalline coaly matter, their forms re- 

 main distinct, and, under the careful microscopic scrutiny of Professor Quekett, 

 they have exhibited a true coniferous structure. In the arrangement and num- 

 ber of the disks upon the fibres, they approach near to the Araucarian group. 

 In general appearance, and even in the mode of preservation, they strikingly 

 resemble certain fossil forms from the Upper Devonian rocks of Saalfeld in 

 Germany, collected by Dr. Richter, — such, for instance, as the Aporoxylon of 

 Professor linger ; but this differs in being of simple structure, and possessing 

 no pores or disks on the woody fibre. 



These fluted fragments are without doubt stems ; and similar but more slender 

 specimens found with them are as clearly the branches, which have borne whorls 

 of smaller twigs, like their living representatives. Again, large branching woody 

 roots, fig. 13. 5, but destitute of superficial niarkings, appear to have belonged to 

 the same trees, and are often several feet long. With these occui* very many 

 specimens of a Lepidodendron, 4, with short scaly leaves — L, nothum, linger ? 



