46 REPORT — 1867. 



1. Eryon, Desmarest. 



aiitiquus, Brod. sp. 



Moorei, H. "W. 



2. Palinurina, Miinst. 



jij^f/mcea, Miinst. Upper Lias, Ilminster. 



longipes, Miinst. Upper Lias, Ilminster, 



3. Penceus, Fabricius. 



latipes, Oj^pel. Upper Lias, Ilminster. 17^ 



4. Eryma, Meyer. 



< elegans, Oppel. Upper Lias, Ilminster. 



Greppini, Oppel. tipper Lias, Ilminster. 



fuciformis, Oppel. Upper Lias, Ilminster. 



5. Hefriga, Miinster. 



Frischmanni, Oppel. Upper Lias, Ilminster. 



6. Glypluea, Meyer. 



Heeri, Oppel. Upper Lias, Ilminster. 



7. Pseudoglyphcea, Oppel. 



Winwoodi, H. W. Lias, "Weston. 



(Figures and specimens of these new species were exhibited.) 



The above list shows an addition to our Liassic Crustacea of seven genera, 

 and probably nine species new to Britain. 



It is extremely interesting to notice so many forms common to our Lias 

 and to the Lithographic stone of Solenhofen in Bavaria. 



The persistence of such forms as Eryon, Eryma, and Qlypluxa through 

 the whole Oolitic series seems clearly to demonstrate that having escaped 

 total extinction in the Lower Lias sea, they migrated from time to time to 

 more favourable areas, and thus were enabled to live on during the periods 

 of time I'cpresented by the long series of deposits from the Lower Lias to the 

 Lithographic stone, in which so many examples are found fossil. 



Oolitic forms of Decapoda Brachyura. 



The genus Prosojwn was established by H. von Meyer for certain minute 

 forms of Crustacea from the Upper White Jura of Qirlinger Thai, and other 

 localities in Germany, of which he has described 29 species (see Palaeonto- 

 graphica for December 1860, vol. vii.). In addition to these he has described 

 1 species from the Lower Oolite, 3 from the Coral Rag, and 1 from the Neo- 

 comian. 



Amongst them, however, are placed forms belonging to a widely different 

 genus in no way related to the Corystidte. 



In Professor Bell's monograph on the Crustacea from the Greensand and 

 Gault (Pal. Soc. Mon. 1862) he has figured and described one of these, and 

 has correctly referred it to the Prnnotlicridte, under the generic name of 

 Plagioplithahnus. 



This genus would probably include the following species of H. von Meyer : — 

 Prosopon hehes, P. simplex, P. rostratum, P. spinosum, P. ehngatum, P. de- 

 pressum, P. ohlusum, P. Iceve, P. suhlceve, P. punctatum, P. Stotzingense, P. 

 tuberosum. 



The following are doubtful : P. insigne, P. aquilatwm, P. marginatum, 

 P. grande, P. excisum, P. lingulatum. 



