BRITISH SILURIAN BRACHIOPODA. 195 



quotes StropJiomena peden and S.filosa from the Lower Llandovery, at Mulloch Hill. I 

 believe, hovv^ever, that the specimens so identified are really referable to SL expansa, a very 

 abundant fossil in the district. 



Strophomena expansa was collected by the Geological Survey of Scotland from the 

 Caradoc, at Snar Water, near Leadhills, in Lanarkshire, also from the same formation 

 at Black Burn, Wanlock Water, Leadhills district, Dumfriesshire. 



122. Strophomena grandis, Soio. Dav., Sil. Mon., PI. XLVI, figs, 1 — 3, and 5 — 6 ; 



Sil. Sup., PI. XV, fig. 6. 



Although quoted elsewhere from Scotland, I am not quite certain that it has been 

 collected in the Girvan District. A specimen from the Upper Caradoc at Thraive Glen, 

 found by Mrs. R. Gray, may possibly belong to the species. Another was obtained by 

 the Geological Survey of Scotland at Duntercleugh Burn, Wanlock Water, Leadhills 

 district, Dumfriesshire ; but this identification requires confirmation. The internal cast 

 of the dorsal valve has been found by Dr. C. Callaway in the Caradoc at Marsh Brook, 

 and this has enabled us to complete the illustration of the species. 



123. Strophomena retroflexa, Salter. Dav., Sil. Mon., PI. XLII, figs. 15 — 17. 



This species has been found by Mrs. R. Gray to occur in the Llandeilo, at Craig- 

 head, Balcletchie, and Ardmillan Brae, in Ayrshire. t 



124. Strophomena Waltoni, Dav. Dav., Sil. Mon., PL XLII, fig. 11. 



A specimen which I cannot distinguish from the typical form of the species was 

 obtained by Mrs. R. Gray from the Upper Llandovery, at Cuddyston Glen, in Ayrshire. 



125. Strophomena imbrex, var. semiglobosa, Bav. Sil. Mon., PI. XLI, figs. 1 — 4; and 



var. semiglobosina, Bav. Sil. Mon., PI. XLI, figs. 5, 6 ; 



Sil.Sup.,Pl. XV,figs.9— 11. 



At p. 286 of my ' Silurian Monograph,' I described and figured several specimens of 

 a shell from the Wenlock formation, measuring 25 lines in length by 29 in breadth, and 

 which, although doubtfully referred to Pander's type, differed from it in having its valves 



