BRITISH SILURIAN BRACHIOPODA. 133 



Genus — Meristella, Hall, 1860. 

 Meristella (?) ANGUSTiFRONS, McCoy, sp. Dav., Sil, Mon., PL X, figs. 21, 27. 



Of this species the exterior characters have been fully described at p. Ill of my 

 ' Silurian Monograph.' I was able to ascertain that the shell was possessed of spiral 

 appendages, but I was not able to determine their attachments. 



Hitherto we have not found any British species possessing the characters of the 

 genus Meristella, and are unable to state to what genus the so-termed 31. {?) angusti- 

 frons really belongs. The shell is not rare at Mulloch Hill, Dalquharren, and in other 

 localities of the Girvan Valley, and therefore suitable specimens for internal exami- 

 nations should be sought for and operated upon. 



Meristella (?) Maclareni, Haswell, sp. Dav., Sil. Mon., p. 116, PI. XII, fig. 20. 



We know nothing of the internal arrangements of this species. In all probability it 

 possessed spiral appendages, but they have not been hitherto discovered. 



Meristella (?) crassa, Sow. Dav., Sil Mon., PI. XIIT, figs. 1, 2, 3. 



It has not been determined as yet whether or no this species was provided with spiral 

 appendages, so that the genus to which it really belongs cannot be determined. It has, 

 however, all the appearance of being a spiral-bearing Brachiopod. 



Meristella (?) subundata, McCoy. Dav., Sil. Mon., PI. XIII, fig. 4. 



This species is no doubt a spiral-bearing Brachiopod, but neither its spirals nor 

 attachments have been worked out. 



Meristella (?) furcata, Sow., sp. Dav., Sil. Mon., p. 119, PI. XIII, figs. 7, 8, 9. 

 No spirals have been as yet discovered. 



Atrtpa (?) HEMisPH^RicA, Sow., sp, Dav., Sil. Mon., PI. XIII, figs. 23 — 30. 



This belongs in all probability to Prof. Hall's genus Leptoccelia, but hitherto the 

 internal characters of that genus have not been completely established. Consequently 



