﻿PLATE XVIII. 



I. Athyris Royssii, L'Eveille. This figure represents the original example of Phillips's 



Spirifera glabristria^ from the Carboniferous limestone of 

 Bolland. British Museum. The outer layer of the shell, with 

 its spiny investment, is absent. 

 3 — 7. — — From Millecent, Ireland. The outer layer of the shell is 



absent. 



8 — 10. — — Three specimens showing a portion of the spiny investment, from 



Carboniferous shales. Ulverstone, fig. 11, being an enlarged 

 representation, to better explain the character of the spines. 



II. — — This is drawn from Phillips's original example of Sp. fimhriata, 



and was communicated by the author. 



12. — squamigera, Be Koninck. From the Carboniferous limestone of 



Millecent in Ireland. I have seen many 

 examples of this shell from both Ireland and 

 England ; and Prof, de Koninck, to whom I 

 communicated specimens, believes that it might 

 perhaps be referable to his species. The outer 

 or reticulated surface of the shell is, however, 

 absent. 



13. — — From the Carboniferous limestone of Ballina, County 



Dungarvan, Ireland. In the collection of Sir 

 R. Griffith. This is the specimen which Prof. M'Coy 

 described (in his 'Synopsis'), as the Martinia phalana of 

 Phillips, but beside not being a spirifer, it does not belong 

 to Phillips's Devonian shell. 13 shows a small portion of 

 the imbricated surface. 



14. Retzia Ulstrix, Be Koninck. From the Carboniferous limestone of Bolland. 



British Museum. 



15. — — From the Carboniferous limestone of Wetton, in Derby- 



shire, and collection of the School of Mines. This shell 

 has been identified by Prof, de Koninck as belonging to 

 his species. 



