Vol. 56.] POKMATION AND ITS GRAPTOLITE-FAUNA. 491 



Figs. 23 & 24. M. uncinatus, var. orbatus nov. 23 a, b. Trefnant-Middletown 

 Brook (Loc. 5 in PI. XXVI). 



24. Var. micropoma (Jsekel). 24 a. Elton -Ludlow Eoad. 

 24 b. Road above Garbett's Hall, Long Mountain. 

 Fig. 25. M. scanicus, Tullb. 25 a. Aberedw Hill (Loc. 7 in fig. 6, p. 435). 

 25 b. Aberedw Hill (Loc. 3 in fig. 6). 



26. M. crinitus, sp. nov. Lower Winnington Lane, Long Mountain. 



27. M. bokemicus (Barr.). 27 a. Kiver Irfon, Builth. 27 b. Aberedw 



Hill. 



28. M. Nilssoni (Barr.). 28 a. Adferton. Coll. J. Hopkinson. 28 b. 



Elton-Evenhay Lane. 



29. Retiolites spinosus, sp. nov. Vicarage Road, Builth (Loc. c' in fig. 5, 



p. 432). 



30. Metiolites (Gothograptus) nassa, Holm. Borek, Bohemia. 



Plate XXVI. 



Geological Sketcb-map of the Long Mountain District (Northern Area) on 

 the scale of 3 inches to the mile. 



Discussion. 



Mr. Hopkinson said that, although he had worked out the zonal 

 distribution of the graptolites of the Lower Ludlow rocks in the 

 neighbourhood of Ludlow, and had communicated two papers on 

 the subject to the British Association, also describing and figuring 

 several new species in La Touche's ' Geology of Shropshire,' he had 

 not been able, in the tew short visits which he had paid to the district, 

 to arrive at results which he considered worthy of being brought 

 before the Society ; and he was pleased to find that what he had 

 failed to do was accomplished by the Authoress. He could assign 

 an approximate position in the Ludlow mudstones to a few species 

 wherever collected in that area, but there were certain difficulties 

 which he had been unable to overcome. In the first place, it was 

 necessary to confirm the results from this area by working out the 

 zonal distribution in other areas ; then there was the difficulty of 

 being certain as to the identification of some of Barrande's species, 

 which could only be overcome, as it had been by the Authoress, by 

 an actual examination of Barrande's specimens ; and, lastly, he had 

 been unable to determine the precise horizon of the Cladophora 

 found at Bow Bridge near Downton, and, so far as he knew, 

 nowhere else in the Lower Ludlow rocks in this country. It 

 was stated in the paper that Monograptus was the only genus 

 represented, but that was the case only so far as the Ehabdophora 

 are concerned, for here were found species of Oallograptus, Dendro- 

 graptus, and Ptilograptus. He thought that this Cladophora-bed 

 was just below the zone of Monograptus leintwardinensis — that is, 

 nearly at the top of the Lower Ludlow. He had found a fragment 

 of a graptolite above Aymestry Limestone, but he could not be 

 certain that it was above the Aymestry Limestone, for the shale 

 in which he found it may have been between the two beds of 

 limestone, the upper bed not showing. It was certainly the fact 

 that the beds became more calcareous as the summit of the 



