BEITISH FOSSILS. 



s 



the eye, and cuts the small triangular neck segment in a line which 

 turns obliquely inwards (see fig. 8, a). The inner corner, therefore, of 

 this free cheek has a projecting angle inwards, and this has a pro- 

 minence just at its tip. The under side of the head (fig. 7) shows 

 a flat and rather broad rostral portion of a transversely elliptical 

 shape, pointed at the ends ; it is crossed by distant strong sharp- 

 edged striae, about nine or ten in number. 



British Locality and Geological Position. — Llandeilo Flags.. 

 Limestone of Portrane, county of Dublin (Coll. GeoL Survey). 



51GLINA— SP. Fig. 8. 



The specimens fi-om Ireland just described show only the head, 

 and for thorax and tail we have recourse to two specimens from 

 Wales, which are certainly referable to the same genus, but only 

 doubtfully so to the present species. The first (fig. 8), measuring four 

 lines in length, shows the characteristic head and eyes of the genus 

 joined to a thorax of six rings. The segments are narrow in pro- 

 portion to their width, but this is in part due to slaty cleavage. 

 The axis is not much arched, it is by far broadest in front, where it 

 is two or three times the width of its abbreviated pleura ; it is nar- 

 rower backwards, and the pleurae on the other hand increase in 

 length ; a strong axal furrow separates the wide axis from the sides. 

 The pleurae are grooved rather more deeply, owing to pressure ; 

 they are facetted anteriorly, and have the fulcrum placed at about 

 one third from the axis, from which point they bend a little back- 

 wards and downwards. The front pleura is more strongly facetted, 

 more bent back, and has the fulcrum nearer the axis than any of 

 the rest, it is also somewhat wider than the others ; all are blunt at 

 the terminations. 



The entire thorax in this specimen is equal in length to the head, 

 but this latter part is so imperfect, that we cannot tell whether the 

 glabella was prominent, and divided by a strong sulcus from the 

 eyes ; it appears not to have been so, and if this be the case, it 

 must belong to a different species ; it is however too imperfect to 

 name. 



Locality and Geological Position. — Llandeilo Flags. Black 

 slate underlying the limestones, at Stoneyford, near Haverfordwest^ 

 Pembrokeshire ; (in company with Graptolites). 



The other and more perfect specimen, found in Anglesea, North 

 Wales, is so much larger than the jE. mirahilis, that in the absence 



