1866.] WOODWAED EEYON. 495 



for certain forms of Astacidce, with extremely broad and flat cara- 

 paces, found in the Lithographic stone of Solenhofen, one of the 

 earliest known geological locahties on the continent, and perhaps 

 the most prolific in its yield of organic remains. 



Only one species was then determined — the Eryon Cuvieri of 

 Desmarest (Macrourites arctiformis of Schlotheim (1820), Locusta 

 marina of Bajer (1757), and first figured by Knorr and Walch 

 in 1755). Since that time Herr Germar, Count Miinster, H. von 

 Meyer, Professors M'Coy and Quenstedt have each contributed new 

 species. Lastly, the late Dr. Albert Oppel, of the Eoyal Bavarian 

 Museum, Munich, a Foreign Correspondent of this Society (whose 

 early death we must aU lament*), has collected, revised, and added 

 to our knowledge of this genus, so that in 1862 (the date of his 

 book) the list of recorded species amounted to fourteen f. 



Professor M'Coy was the first to record an English species of this 

 genus, the Eryon Barrovensis, from the Lias of Barrow-on-Soar, 

 Leicestershire. [See the * Annals and Magazine of Natural His- 

 tory,' 1849, p. 172.] But as his description varies in some points 

 and is unaccompanied by a figure, I have ventured to delineate it 

 by the help of the fine examples in the cabinet of the Rev. P. B. 

 Brodie, F.G.S., and those in the British Museum. I also subjoin a 

 revised description of it, and notices of other British species of this 

 genus from the Lias and Oolite, collected and lent by Charles 

 Moore, Esq., E.G.S., of Bath, Captain Hussey, of Lyme Regis, and 

 from specimens in the British Museum obtained by E. C. H. Day, 

 Esq., F.G.S., formerly of Charmouth. 



Erton", Desmar. 1822. 



Coleia, Broderip, 1835, Trans. Geol. Soc. 2nd ser. vol. v. t. 12. 

 f. 1 & 2. 



1. Eeton antiquus, Brodp., sp. 



Although unwilling to abolish a genus named in honour of so 

 great a geologist as the Earl of Enniskillen, I am compelled to 

 endorse the decision of my late friend Dr. Albert Oppel, and make 

 this the first and largest English species of the genus Eryon {Eryon 

 antiquus, Brodp. sp.)^. 



From the Lias, Lyme Regis. 



2. Eeyon Baeeovensis, M'Coy, 1849. PI. XXY. fig. 1. 



The carapace of this species (like that of its congeners) is extremely 

 flat, about one- eighth broader than long, the posterior margin is 

 truncated, the lateral margins are fringed with minute spines ; two 

 indentations intersect the border on either side (the first being some- 

 what behind, and the second upon the line of the cervical furrow), 

 and enclose between them a short rotundato-quadrate lobe. 



* Dr. Oppel died on 22nd December, 1865, at the early age of thirty-four 

 years. 



t Vide Palaontologische Mittheilungen aus dem Museum des Kon. Bayer. 

 Staates, von Dr. Albert Oppel : Stuttgardt, 1864. 



t See Oppel's Pal. Mittheil. p. 11. 



