6 Bolton, Palcsontology of the Manx Slates. 



however, that Dr. Dawson was guided in his determination 

 by the description and figure, and not by an examination 

 of the specimen. 



In 1892 the intaglio cast of a trilobite was found by 

 the writer* in a crush-conglomerate at Ballastowell, near 

 Ramsey, and in 1893! ^ ^^^ other fossils {pictyonenia and 

 Dendi'ograptus) were added from the slates of Cronk 

 Sumark, near Sulby Glen station. 



From the foregoing it will be apparent that the suite 

 of fossils recorded from the Manx slates are of a doubtful 

 character, without much support from positive evidence, 

 and requiring further investigation. 



If we consider, in the first place, the supposed plant 

 remains, we find that all the earlier workers made allusion 

 to " fucoids," but that Binney was the only one to attempt 

 a description of what he saw. 



Prolonged research amongst the slates by many 

 recent workers has revealed no trace of true fucoids, and, 

 as we shall see later, the supposed fucoids were, in all 

 probability, the casts and tracks of Palcsochorda. In the 

 absence of descriptions, figures or specimens, we are 

 forced to reject the supposed fucoidal structures of 

 Taylor, Grindley and others. 



Psilophyton monense of Binney calls for more atten- 

 tion. It was described as follows : " The stem is thick, 

 dichotomous, divisions variable in distance, the terminal 

 ones short, pointed, nearly equal in size and length, surface 

 nearly smooth. The branches in the lower part are thick 

 comparatively to their length. The surface of the stem 

 appears to be smooth, and affords no evidence of striae or 



♦ " On the Occurrence of a Trilobite in the Skiddaw Slate of the Isle of 

 Man." Geol. Maq., Dec, 30, Vol. x., 1893, P- 29. 



t "Observations on the Skiddaw Slates of the Isle of Man." BriL Assoc. 

 Rep., Notts, 1893. 



