502 PEOCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 23, 



doubt their consanguinity, yet the former has died out, and the 

 latter remains to this day. 



The Scyllaridce, which take their place at the present day, have 

 only a mimetic resemblance to them, the simulation being assisted 

 in a great degree by the broad scale -hke form of the outer pair of 

 antennae, which are flattened out and lie in a plane with the cara- 

 pace. They, however, ofl'er some points for comparison, and occur 

 most commonly in the China Seas and on the coast of Japan, asso- 

 ciated with recent Limuli and forms of Palinurus, &c., which are 

 found together in a fossil condition in Bavaria. 



"Where a series of similar forms occur together, fossil and recent, 

 it is fair to infer a similarity of conditions favourable to such a. 

 group. 



The wide tracks of fine argillaceous mud which characterize the 

 enormous rivers of China, the coast, and its adjacent islands, agree 

 well with the lithological texture of the Solenhofen beds in which 

 the fossil Crustacea lie imbedded; and the terrestrial conditions 

 evidenced by the remains of Sauria, the Archceopteryoc, and Ptero- 

 dactyles, with countless Libellulce, spiders, and Cycadece of large size, 

 point to a continent close at hand, the rivers of which brought down 

 the periodic mud- avalanches which entombed the cuttlefishes and 

 Crustacea in such quantities both at Pappenheim and Solenhofen. 



By referring to the preceding Table, it will be seen that only three 

 continental species of Eryon (E. Escheri, Edwardsi, and Hartmanni) 

 occur in the Lias, the remainder being from the Lithographic Stone 

 (Upper Oolite). 



We ought then, T think, either to find many more species in our 

 Oolite, or to regard the lithographic species as the representatives 

 of our Liassic forms in Bavaria. 



A comparison of further genera and species from the Lias will show 

 that we have representatives of nearly every form from Solenhofen 

 in our Lias beds. 



EXPLANATION OF THE PLATES 



{Illustrative of the genus Eryon). 



Plate XXIV. figs. 2-4. 



Fig. 2. Carapace of Eryon Brodiei, H. Woodw. Lower Lias, Lyme Regis. Two- 

 thirds the natural size. Collection of the British Museum. 



3. Eryon Wilmcotensis, H. Woodw. Lower Lias, Wilmcote. Natural size. 



Collection of R. F. Tomes, Esq., F.Z.S. 



4. Eryon Oppeli, H. Woodw, Lithographic stone, Solenhofen. Natural 



size ; from the original in the British Museum. 



Plate XXV. figs. 1-3. 



Fig. 1. Eryon Barrovensis, M'Coy. Lower Lias, Barrow on Soar, Leicestershire. 

 One-half the natural size ; restored from specimens in the collection 

 of the Rev. P. B. Brodie, M.A., F.Gr.S., and in the British Museum. 



2. Eryon crassichelis. H. Woodw. Lower Lias, Lyme Regis. One-third 



the natural size. Collection of Captain Hussey, Lyme. 



3. Eryon Moorei, H. Woodw. Upper White Lias, Ilminster. Twice the 



natural size. Collection of Charles Moore, Esq., F.G.S., Bath. 



