ANNIVERSARY ADDRESS OF THE PRESIDENT. 



97 



Lingulella ferruginea, Salt., and var. ovalis, Hicks, Orthis sagittalis, 

 and Distinct pileolus. The special or restricted forms are only 2 — 

 Discina cacrfaiensis, Hicks, MS., and Lingulella primaiva, Hicks. 

 The Plants ? and Protozoa are mentioned nnder those heads in the 

 analysis. The table shows that 8 out of the 14 classes are not repre- 

 sented in the Harlech group. That they will remain so under re- 

 newed search and scrutiny I much doubt. Each year adds some 

 new form to these once believed to be unfossiliferous strata. North 

 Wales has yet to yield up from these rocks a fauna equal to that 

 of South "Wales. 



Menevian. — Table II. gives us all that is known of the Menevian 

 fauna and its relation to the Harlech series and the succeeding 

 Lower Lingula-flags, of which, indeed, it is but the base ; for out 

 of the 24 genera and 51 species in the Menevian, 13 of the former 

 and 19 of the latter are common to the two. Of the Crustacea 8 of 

 the 12 known genera, including 14 species, are the same — viz. 

 Agnostus (A. Daviclis, A. scutalis), Anopolenus {A. Eenrici, A. Sal- 

 ter i), Conocoryphe (C. applanata, G. humerosa, O. variolaris), Holo- 

 cephalina (H. primordialis), Leperditia (L. HicJcsii), Primitia (P. 

 solvensis), Microdiscus (M. punctatus), Paradoxides (P. aurora, 

 P. Davidis, and P. Hicksii) ; and 3 of the 4 genera of Brachiopoda, 

 Lingulella (L. ferruginea), Obolella (0. maculata), and Orthis (0. 

 sagittalis). Of the 6 species of Pteropoda, only 1 is common to the 

 2 groups, namely Theca corrugata. The Menevian is united to 

 the Harlech and Longmynd rocks through 8 genera and 12 species. 

 The Crustacea by 3 genera with 4 species, viz. Agnostus (cam- 

 hrensis), Conocoryphe (hufo), Paradoxides (P. aurora and P. Hicksii) ; 

 and the Brachiopoda the same, Discina (pileolus), Lingulella {fer- 

 ruginea and var. ovalis), and Orthis (sagittalis). The Lyssakine 

 sponge (Protospongia) and Theca penultima complete the alliance. 

 8 of the 14 classes are not represented. The first Cystidean, 

 Protocystites menevensis, Hicks, occurs in the Menevians of St. David's. 

 11 new genera (not known in the Harlech group) first occurred in 

 the Menevian sea ; 6 are Crustacea, 2 Pteropoda, 1 Cystidean, 1 An- 

 nelide, and 1 Brachiopod ? jSTo species pass from the Menevian to 

 the Middle or Upper Lingula-flags. 



Lower Linofla-elags. — Table III. But for the Crustacea, the 

 Lower Lingula-flags would have no value as a subformation ; they 

 are but the upper, continuous development of the Menevian. Only 

 one genus of Crustacea, the Phyllopod Hymenocaris, is new to the 

 Lower Lingula-flags ; the remaining 8 are also Menevian ; and 14 of 

 the 25 crustacean species also occur in the Menevian below. Still 

 further, of the 17 known Lower Liu gula-flag genera, 13 are Mene- 

 vian ; and this close association is more marked still from the fact 

 that only 2 species pass to the Middle and 8 to the Upper Lingula- 

 beds ; so that there is a greater difference, between the Lower and 

 Upper Lingula-beds themselves than between the former and the 

 underlying Menevian. The Upper Lingula-flags, through their 

 Crustacea, 8 genera and 30 species, stand alone. 



Upper Lingtjla-elaos. — Table IV. Out of a community of 17 



