82 



PKOCEEDIN'G-S OF THE OEOEOGTCAL SOCIETY, 



UPPEE LeN t GTJLA-ELAGS. 



Plants. — None known. 

 Pkotozoa. — None occur. 



Hydeozoa. — Dictyonema sociale occurs abundantly in the grey and 

 dark shales of Keys End Hill, Malvern, and in North Wales. Whether 

 Dictyonema should be placed with the Hydrozoa or Bryozoa is still 

 a doubtful question. Salter in 1857 separated this genus from 

 Kjerulf's genus Fenestella and also from Hall's genus Graptopora. 



Actctozoa. — None. 



E CHTisroDEEM ata . — Non e. 



Atoteleda. — 2 genera, Scolicoderma antiquissimum, Salt., and Ser- 

 pidites fistula, Holl. The Hollybush sandstone of the Malverns is 

 characterized by the two Annelides above named ; the Hollybush 

 beds of the Wrekin also contain Annelide remains. S. fistula first 

 appears in the Menevian beds. Whatever may be the age of the 

 Hollybush sandstones, these two species occur in the Malvern area, 

 at the base of the Upper Lingula-flags. 



Cettstacea. — No less than 30 species represent the following eight 

 genera — Agnostus 5 species, Ampyx 1, Anopolenus 1, Conocoryplie 9, 

 Dihelocephalus 2, Microdiscus 1, Olenus 9, Paradoxides 2*. 4 species, 

 viz. Agnostus princeps, Ampyx prainuntius, Conocoryplie depressa, and 

 Olenus alatus, pass from the Upper Lingula-flags to the Lower Tre- 

 madoc'; and 20 species are confined to this horizon. Thus the Upper 

 Lingula-flags through their Crustacea become of much importanc, 

 and the few (4) that pass to the Tremadoc clearly show the strati- 

 graphical value of the Lingula group and its distinctness. It may be 

 worth stating that 4 species in the Upper Lingula-flags also occur 

 in the Menevian : they are Anopolenus Salteri, Microdiscus punctatus, 

 Paradoxides aurora, and P. Hicksii ; only 2 species of the 4 that 

 pass from the Upper Lingula-flags to the Tremadoc extend up into 

 the Upper Tremadoc, namely Agnostus princess and Ampyx prce- 

 nuntius. 



Bryozoa. — Dictyonema sociale, Salt., is the only Bryozoon known 

 in the Upper Lingula-flags ; it passes to the Lower Tremadoc, both in 

 the North and South Welsh areas, at Tremadoc and St. David's; it is 

 highly characteristic of the pale Dictyonema-shales that overlie the 

 black shales in the valley of the White-leaved Oak at the southern end 

 of the Malvern rangef. These black and pale greenish Upper Lin- 

 gula shales are about 500 feet thick, and contain a singular fauna 

 of Crustacea and Brachiopoda. Prof. Phillips first noticed these 

 shales and their fossil contents. The Crustacea are Conocoryplie 

 malvernensis, PhilL, Olenus bisulcatus, Phill., 0. humilis, Phill., 0. 

 spinulosus, Phill., and 0. pauper, Phill., Sphcerophtliahnus pecten, 

 Salt., Agnostus M'Coyi?, Salt., and A. princeps ; the Brachiopoda are 



* For list of the species see p. 8o, last paragraph in the Lower Lingula-flag 

 division. 



t It is possible that Kjerulf's Fenestella socialis from Scandinavia may be our 

 Dictyonema; Eichwald's Gorgonia flabelliformis, although much larger, is almost 

 identical ; Mr. Salter, however, established its generic distinctness. 



