15 



Moffat valley, and by means of confirmatory sections places 

 his conclusions beyond all doubt. The various sub-divisions, 

 lithological characters, and fossil zones are treated in great 

 detail ; a table showing the vertical distribution of the 

 fossils is given, and the respective faunas of the three divisions 

 of the Moffat series are compared with their foreign 

 equivalents/' 



4. The Girvan Succession (26). 



In order to submit his Moffat conclusions to the severest test 

 that he could devise, Lapworth now turned to the Girvan district, 

 a region so difficult that, in spite of much field work by many 

 observers, and of the extensive Gray collection of fossils, *" Professor 

 Ramsay .... unable to reconcile the numberless dis- 

 crepancies between the apparent sequence, palaeontological and 

 stratigraphical, as here developed and that worked out by himself 

 in the regions of Siluria, has been driven to the conclusion that these 

 Scottish rocks belong to an episode of a date between that of the 

 Bala and the Llandovery, unrepresented among the fossil-bearing 

 rocks of the South of Britain." " If/'f Lapworth proceeds, " the 

 asserted heterogeneous intermixture of fossil assemblages of all 

 types, elsewhere characteristic of distinct horizons, were actually 

 found to obtain amongst them, palaeontology might well abandon 

 her claim to be the unfailing handmaid of stratigraphy among the 

 more ancient formations. If, on the other hand, the cautious 

 study of these deposits led to the demonstration of the contrary 

 opinion i.e., that their distinct fossil assemblages were restricted, 

 as in other lands, to different stratigraphical zones, British geologists 

 would feel justified in attempting the correlation of their own 

 Lower Palaeozoic subformations with their nearest representatives 

 all over the world." 



Work had apparently been begun in the Girvan district before 

 1876, but Lapworth now resolved to attack this ground with the 

 same exhaustive thoroughness as he had evinced at Moffat. He 

 naturally employed the same methods as before, the individualisa- 

 tion of mappable bands, detailed stratigraphy and mapping, zonal 

 collection, and especial attention to the faunas of bands in which 

 he discovered graptolites. As the result he worked out a complete 

 succession of strata beginning with the Lower Llandeilo or Arenig 

 and ranging up into the Tarannon beds. The graptolitic bands 

 followed one another in the same sequence as those of Moffat. 

 Not all of them, however, were represented here, and between 

 and among them were strata bearing brachiopods, trilobites, and 

 other fossils which could with some reservations be compared 



* 26, p. 541. f 26, pp. 542-543. 



