ON THE FOSSIL PUYLLOPODA OF THE PALEOZOIC BOCKS. 67 



After describing Myocaris hdraria as a bivalve crustacean related to 

 Cerafwcaris, in the ' Quart. Journ. Geol. Soc.,' vol. xx. (18G4), p. 292, 

 Mr. Salter stated with regard to Ribeiria, that ' the strong internal sub- 

 cardinal ridge, marking the position of the cervical furrow, leads me to 

 suspect that liibeiria, a Lovver-Silnrian genus which has not yet found 

 its place, may be a cognate form. A univalve carapace would be nothing 

 remarkable among the allies of Nehdlia, but is very puzzlino- if referred 

 to Lamellibrancli, while the whole aspect is unlike tliat of any of the 

 Calyptrseiform shells. I think that we may have here the true affinity, 

 but the suggestion is only given to induce research. The strong muscular 

 scar behind the beak is asrainst it.' 



Salter, however, seems to have regarded Eiheiria as a mollusc in 

 1866, ' Mem. Geol. Survey ,' vol. iii. p. 346, where his Eiheiria complanata 

 (pi. 11b, fig. 16), from the Lower Llandeilo of Shropshire, is described; 

 but with the words ' There is some uncertainty as to the group to which 

 this curious fossil belongs.' In ' Silnria,' also, in the '4th' (really the 

 3rd) Edition, 1867, at pp. 48 and 49, it seems to be regarded as a mol- 

 lusc : but at p. 521 its molluscan position lias a note of interrogation. 

 Baily ('Figures of Characteristics of Biitish Fossils,' Part 1,'^1867) 

 copied Salter's figure and placed it in the Conchifera, p. 21, pi. 8, fig. 9. 



E. Billings, in ' Canad. Geol. Surv., Pal. Foss.', vol. i. (1865), referring 

 sorne fossils to Sharpe's liibeiria, but of uncertain alliance (' incertce 

 sedis ') and, if subgenerically distinct, to be provisionally named Biheirina, 

 regarded them as being possibly byssns-bearing molluscs. These were 

 Bibeiria (?) calcifera, p. 340, fig. 326, and B. (?) loncjiuscula, p. 340, fig. 



^In Dr. Bigsby's 'Thesaurus Siluricus,' 1868, p. 141, Eiheiria, Sharpe, 

 1853, is catalogued as a Dimyarian Mollusc, with the following species: — 



CCtlctTSTCL I 



long'iuscula J ^i'^'^g^- Calciferous Sandstone ; Grenville, Canada. 

 complanata, Salter. Lower Llandeilo ; Salop. 

 ZX^^l ] ^^'^^^- Budleigh-Salterton pebbles. 



pholadiformis, Sharpe. Fauna D d, 1, 4, 5, Caradoc ; Portugal, 

 Spain, Bohemia. 



At page 168 Bibeiria is grouped with the Gasteropoda, and B. 

 Sharpei, Barrandc, D d, 3, Bohemia is added. 



Under the heading of ' Phyllopodes ' belonging to the Gres de May 

 (Calvados) M. G. de Tromelin has cited two species of Bibeiria. In the 

 ' Bullet. Soc. Linn. Normandie,' ser. 3, vol. i., 1887, p. 35 and p. 74, IM. G. de 

 Tromelin stated that Mr. Salter had named but not described two species 

 of Bibeiria from Mr. Vicary's coliecti(m of the pebbles from Budleio-h- 

 Salterton, and which had been found also in the May Sandstone'^ of 

 Normandy, namely:— 1. J?, covfortnis, Salter, Bigsby, ' Thes. Silur.' p. 

 141 (1868) ; Tromelin and Lebesconte, ' Bullet. Soc. Geol. France,' ser. 

 3, vol. iv., table D, No. 43, 1876. B. Bussacemis [pholadiformis], Sharpe, 

 Q. J. G. S., vol. ix. pi. 9, fig. 17 (1853). From May and Jurques 

 (Calvados). 2. B. mof/vifica, Salter, Bigsbv, op. cit. (1868) ; Trom. and 

 Lebesconte, No. 42 (1876). From Com pa nd re (Calvados). 



In Nicholson's 'Manual of Palajontology,' 2ud edit. 1879, vol. i. p. 

 351, the zoological position o( Bibeiria is left doubtful. 



F 2 



