420 MISS B. M. R. WOOD ON THE LOWER LUDLOW [May I9OO, 



district. Three of these were species previously noted and named 

 by Mr. Hopkinson in manuscript, namely M. leintwardinensis, 

 M. Salweyi, and M. serra, and two belonged to forms which were 

 referred to M. colonus and M. JRcemeri. 



In his paper on the ' Geological Distribution of the Bhabdophora/ 

 published about the same time, Prof. Lapworth recorded M. scanicus, 

 Tullb. from the English Lower Ludlow Beds ; and paralleled for the 

 first time with the Lower Ludlow of Britain the beds Ee2 of Bohemia, 

 containing M. bohemicus, M. chimcera, M. colonus, M. Roemeri, and 

 M. priodon; and also the M. colonus-zone of Scania with if. bohemicus, 

 M. colonus, M. Nilssoni, and M. scanicus. 



In 1883 Tullberg, 1 besides completing the stratigraphical work 

 mentioned on p. 418, thoroughly revised the species of graptolites 

 found in the CardiolaSkiffer of Scania. He figured and described 

 the species which had been previously recorded from these beds, 

 and also two new forms, M. scanicus and M. uncinatus. 



In 1884 J. D. La Touche, in his ' Handbook of the Geology of 

 Shropshire/ figured and described several species of graptolites from 

 the Lower Ludlow Beds of Ludlow. Among these were three of 

 Mr. Hopkinson's species, M. clavicula, M. capula, and M. retusus, 

 previously named only in manuscript. 



In 1889 Jsekel'" cited several graptolite-species from the 'Grapto- 

 lithengestein ' (Drift) of Northern Germany. From his list it is 

 clear that the fauna of these beds is mainly of Lower Ludlow age. 

 Two new species, M. frequens and M. micropoma, together with 

 other forms, were described and figured. 



In 1897 appeared Prof. Freeh's monograph on the graptolites. 3 In 

 this work he figured and described most of the species of graptolites 

 previously recorded from beds of Lower Ludlow age. 



The latest addition to our knowledge of the Lower Ludlow 

 graptolite-fauna was made in 1899 by Dr. Perner, 4 who figured and 

 described all Barrande's type-specimens, and thus helped to remove 

 many of the difficulties which previously hindered correct identifica- 

 tions of the English forms with the Bohemian species. Several 

 new species and varieties are recorded by him from the upper beds 

 of Etage Ee 1 and ~Ee 2, the collective fauna of which corresponds 

 remarkably with that of the Lower Ludlow Beds of Britain. 



III. General Stratigraphy of the Lower Ludlow Formation. 



Before describing the several districts which I have examined in 

 detail, I may here state briefly the main stratigraphical problems 

 offered by a study of the Lower Ludlow Group. Two of these 

 problems are of special importance, namely : — 



(1) The determination of the stratigraphical lower and upper limits of 



the Lower Ludlow Group ; and 



(2) The natural zonal divisions of the group. 



1 ' Skanes Graptoliter ' pt. ii, Sver. Geol. Undersokn. ser. C, no, 55. 

 ■ ' Ueber das Alter des sog. Graptolithengesteins ' Zeitschr. d. Deutach. Geol. 

 Gesellsch. vol. xli, p. 653. 



3 ' Lethsea Geognostica ' vol. ii, pts. ii-iii. 



4 * Etudes sur les Graptolites de Boheme ' pt. iii. 



