Fearnsides, Elles, Smith — Palceozoic Rockn of Pomerot/. 117 



with their rich Trinucleus fauna, while the highest sub-division, the 

 Thraive beds, presents many analogies with the Tirnaskea beds. 



With other British areas of Ashgillian rocks, we might institute 

 similar comparisons ; but the lithological characters are so different 

 that, until more is known of the faunas, such comparisons are of little 

 Yalue ; and beyond noting that the classification of the Lake District 

 Ashgillian into a lower division characterized by Strophomena siluriana 

 and the Keisley type of fauna, and an upper characterized by Fhacops 

 mucronatus, appears to hold good, we content ourselves with referring 

 to Dr. Marr's paper on the Ashgillian series in the "Geological 

 Magazine " for February, 1907. Our main fossil-bearing horizon, the 

 Killey Bridge beds, is intermediate between these two divisions ; and 

 as it is therefore somewhat newer than either the Keisley or its 

 equivalents, the E-hiwlas, the Eobeston Wathen, or the Chair of 

 Kildare limestones, it is not surprising that its faunistic assemblage is 

 more like that of the Brachiopod (Ashgillian) shales of Sweden than 

 of any yet described British Caradocian bed. The general relations of 

 the faunas of our sub-divisions are best seen by reference to the 

 following Table I. The species indicated by a star are peculiar to 

 Pomeroy. 



[Table I. 



