160 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 6, 



the perforations large and squarish, and the tail also is small, smooth, 

 and with the point a little incurved. In all these particulars it agrees 

 with M. Rouault's species ; although in his specimens the branched 

 head-spines were the rule, and the simple ones the exception. 



8. Ogygial glabrata, n. s. Pl. VII. fig. 4. We are induced to 

 give a name to this very distinct fragment, as there appears to be no 

 pubhshed species to which it can be referred. It is equally likely to 

 belong to the genus Asaphus. 



Tail an inch and a half wide, semicircular, -with the sides very 

 shghtly flattened ; the axis gently convex, not quite half the width 

 of one of the sides ; it extends nearly three-quarters of the length of 

 the tail, and then runs out for a further distance into a conical ap- 

 pendage, which fades into the general depressed surface. The upper 

 part of the axis is marked by three faint rings, the rest smooth ; sides 

 with four or five flattened ribs (besides the broad upper articulating 

 margin) separated by narrow sharp radiating furrows, which do not 

 reach much more than half-way to the margin. Surface quite smooth, 

 except a few concentric lines near the margin, and some obscure 

 transverse lines on the middle of the axis. 



As Mr. Sharpe gives me full permission to revise his former list of 

 fossils from Vallongo, vol. v. p. 146, I will add that there occur at 

 that locality — 



1. Calymene Ttistani, Brongn. 



2. Arago, Rouault. 



3. Asaphis Guettardi*, Brongniart? 



4. Desmaresti, Brongn. (0. Edwardsi, Rouault). 



5. Asaphus, a species probably quite new, with extremely wide tail 

 and a short axis (jsofelus Powisii of the former list). 



6. Illeenus giganteus, Burmeister (/. Lusitanicus, Sharpe). 



7. Placoparia Zippei, Boeek? (Cheiruj'us of former list). 



Appendix D. — Notes on the Entomostraca. 

 By T. Rupert Jones, Esq., F.G.S. 



Beyrichia Bussacensis, n. s. 



This Beyrichia abounds in a schistose rock from Porto de Louza, 

 Serra de Bussaco, and from the Serra de Mucela, belonging to the 

 Lower Silurian group, and is closely allied to B. complicata (Salter) 

 of the Lower Silurian rocks of N. Wales. Casts and impressions 

 of the valves are numerous, but specimens with the external surface 

 are rare. Besides considerable variation in the disposition and rela- 

 tive proportion of the raised ribs and border, the Portuguese form 

 difi'ers from the specimens figured by Mr. Salter and Prof. M'Coy 



* It may be remarked that the original species of Brongniart's genus Ogygia, 

 0. Guettardi, has the characteristic labrum of Jsaphus, and must be restored to 

 that genus. O. Buchii, then, with its entire pointed labrum, will stand tor the 

 type of Ogygia. 



