LOWEE PALEOZOIC ROCKS OF HAVERFORDWEST. 489 



In Scania, Dr. Tullberg (' Skanes Graptoliter,' i. p. 17) finds 

 above his zone with Phacojps mucronatus (P. eucentra) a zone with 

 Di^Jograptus and Climacocjraptus scalaris, and marked by an absence 

 of Monograptiis. This zone he places at the top of the Upper 

 Cambrian (Sedgwick), and not at the base of the Silurian, where 

 Prof. Lapworth describes a zone marked by the absence of Mono- 

 graj^tus, viz. at the base of the Birkhill beds (cf. Lapworth, Q,. J. 

 G. S. vol. xxxiv. p. 318). 



In Westrogothia the gritty beds with Trinucleus at Mosseberg 

 may represent our Slade beds. 



vii. The Conglomerate. — As stated, when describing the apparent 

 position of these beds, they appear to succeed everywhere the Slade 

 beds. 



If this be their true position, they form a satisfactory base to the 

 Silui^ian rocks of this area. 



We may compare them with the Mullock-Hill conglomerate of 

 Prof. Lapworth (Q. J. G. S. vol. xxxviii. p. 621), which lies in the 

 Girvan district directly above the T^rwi«c7«MS-shales, just as the con- 

 glomerate in the district now described lies above our Trinucleus- 

 shales. 



viii. Loiuer Llandovery Beds. — We have applied this term to 

 the shelly sandstones immediately south of Haverfordwest town, as 

 they have been constantly spoken of as Lower Llandovery. If they 

 do actually succeed the Conglomerate stage, the latter should also be 

 included in the Lower Llandovery series. 



These shelly sandstones are lithologically and palseontologically 

 similar to two well-known deposits, viz. the Mullock-Hill Sand- 

 stones of the Girvan district, and stage 5 /3 in the neighbourhood of 

 Christiania. All these contain Nidulites along with Stricliandinia 

 and a host of other brachiopods. A comparison of the published 

 lists will show the practical identity of the faunas {cf. Catalogues 

 of Palseozoic Possils in the Woodwardian Museum, and that of 

 Practical Geolog}^, also Kjerulfs ' Yeiviser '). 



The upper part of the Brachiopod-beds of Westrogothia has i 

 similar fauna, and is placed on this horizon by the Scandinavian 

 geologists. 



One of us has in a previous communication (Q. J. G. S. vol. 

 xxxviii. p. 316) discussed the age of the Lejotceiia-liiiiestone of Mr. 

 Tornquist, which occurs in Dalecarlia, and has referred it to a posi- 

 tion above the Lohiferus- and Retiolites-sh.2lQQ of that region. This 

 was certainly a mistake, due to ignorance of the phenomena pre- 

 sented by a greatly disturbed region at the time of examination. 



Dr. Pr. Schmidt has shown (Q. J. G. S. vol. xxxviii. p. 523) 

 that the fauna of the stage P of the East Baltic provinces is that of 

 the Leptcena-luRQ^ioiiQ of Osmundsberg. 



The Leptcena-lrmestonQ contains a mixture of faunas of several of 

 the Haverfordwest beds, viz. : — the Lower Llandovery, Trinucleus- 

 seticornis beds, and perhaps even of the Robeston-Wathen limestone, 

 the corals of which also occur in the Leptama-lime^touG. 



