44 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Dec. 4, 



The following is a list of the fossils discovered in the Tremadoc 

 rocks of St. David's : — 



Neseuretus ramseyensis, sp. n. 



quadratus, sp. n. 



recurvatus, sp. n. 



elongatus, sp. n. 



, var. obesus. 



Niobe menapiensis, sp. n. 



solvensis, sp. n, 



Theca Davidii, sp. n. 



Orthoeeras, sp. 



Belleropbon ramseyensis, sp. n. 



solvensis, sp. n. 



Palasterina ramseyensis, sp. n. 

 Dendrocrinus cambriensis, sp. n. 

 Ctenodonta menapiensis, sp. n. 



cambriensis, sp. n. 



Paltearca Hopkinsoni, sp. n. 



Palsearca oboloidea, sp. n. 

 Glyptarca primseva, sp. n. 



Lobleyi, sp. n. 



Davidia ornata, sp. n. 



plana, sp. n. 



Modiolopsis ramseyensis, sp. n. 



Homfrayi, sp. n. 



solvensis, sp. n. 



cambriensis, sp. n. 



Lingulella Davisii, M'Coy. 

 Lingula petalon, Hicks. 

 Obolella plicata, Hicks. 

 Orthis Carausii, Salter. 

 Orthis menapise, Hicks. 

 Eophyton explanatum, Hicks. 



Description of the Fossils. 

 JSesettrettts, gen. nov. 



Head semicircular. Glabella tapering forwards, moderately con- 

 vex, and marked by three pairs of furrows, which reach about a third 

 of the distance across, but usually bend backwards at their extremities. 

 Eyes prominent, and situated about halfway up the head. Facial 

 sutures distinct, the anterior run rather obliquely outwards to cut 

 across the anterior margin, and the posterior to the hinder margin 

 almost at the angles. Cheek-plates nearly triangular, rather wider 

 on the outer side, posterior angles slightly produced. Thorax 

 strongly trilobate, and composed of thirteen segments. Pleurae 

 faceted for rolling up. Tail about equal to a fourth of the length, 

 wide, and sometimes truncate at the extremity ; axis prominent, 

 and composed of from eight to ten rings, lobes strongly ribbed. 



In its coniform glabella with lateral furrows it resembles Cono- 

 coryphe ; but in the position of its facial sutures, its very prominent 

 eyes, and in its large many-ribbed and wide tail it is veiy distinct 

 from that genus. The tail seems to ally it to Dil-elocephalus ; but its 

 glabella entirely separates it from that genus. The thorax, which 

 shows characters intermediate between Homalonotus and Calymene, 

 is also peculiar, and unlike that of any other genus. 



Neseuretus ramseyensis, spec. nov. PI. III. figs. 7-10 & 16-22. 



Head semicircular, margined, and with the angles very slightly 

 produced. Glabella parabolic and convex, about one third of the 

 width and rather less than two thirds of the length of the head, 

 and indented deeply by three lateral furrows which bend back- 

 wards at their extremities ; the basal furrows reach nearly to the neck- 

 furrows, and mark off triangular lobes on either side. Eyes pro- 

 minent, faceted, and placed at a distance from the glabella equal 

 to about half its width. Cheek-plates triangular. The thorax 

 (PI. III. fig. 16), which evidently belongs to this species, is strongly 

 convex ; axis tapering, with sharply raised rings ; pleura? grooved and 

 faceted, with the fulcrum situated at about a third of the distance 



