GRIFFITHIDES. 35 



This species, which was founded upon a glabella only by Captain (afterwards 

 General) Portlock, who obtained it from the Carboniferous Limestone of Tyrone, 

 Ireland, is thus noticed by him in his ' Report on the Geology of Londonderry and 

 Tyrone' (p. 311). "Fig. 8 is a larger individual, of probably another species 

 [distinct from longiceps] ; the surface is granular, and it is proportionately flatter ; 

 it may be called Griffithides platyceps." The specimen figured on our PI. VI, fig. 

 13, and enlarged twice the natural size, was obtained from the Carboniferous Lime- 

 stone of Derryloran, Tyrone, the original being preserved in the Museum of the 

 Geological Survey of Ireland, Dublin. 



13. Geiffithides obsoletus, PliilUps, sp., 1836. PI. VI, fig. 12. 



AsAPHtJS OBSOLETUS, PhilHps. Geol. Torks., vol. ii, p. 239, pi. xxii, figs. 3—6, 1836. 



— GEANULIFEEUS, PMlKps. Ibid., fig. 7, 1836. 

 Phillipsia Bhongniabti, J)e KonincTc. Anim. Foss., t. liii, fig. 7, 1842. 



— — Morris. Cat. Brit. Foss., p. 114, 1854. 



— — Salter Sf S. Woodw. Cat. and Chart Foss. Crust., 



p. 16, fig. 113, 1865. 



— — R. Woodw. Cat. Brit. Foss. Crust., p. 55, 1877. 



This species is founded on a very broad and smooth pygidium, nearly one fourth, 

 broader than long, composed of ten coalesced somites, the axis much broader than 

 the pleural portion ; each of the nine rib-like plicae marked by a furrow down 

 the centre (as in the pygidium of G. glohiceps already noticed), the margin of the 

 tail-shield is smooth. 



The glabellal portion of the head, most probably belonging to the same 

 individual (being enclosed in the same piece of matrix), although mutilated, 

 exhibits peculiar and delicate striations over its entire surface. The head (some- 

 what restored) is figured by Prof. Phillips with the pygidium. This specimen is the 

 type of Phillips' figure in the ' Geol, of Yorkshire,' and was at that time in the 

 Gilbertson Collection, and is now in the British Museum (Natural History). 



Formation. — Carboniferous Limestone. 



Locality. — Bolland, Yorkshire. 



The following is Prof. Phillips' original description of his Asaphus obsoletus 

 (op. cit., p. 239) : 



" Abdominal lobes ventricose ; transverse undulations obtuse ; surface smooth 

 with undulating lines ; the limb with oblique undulating strice ; head finely striated, 

 undulated lines roundish and lumpy." 



The name of Ph. Brongniarti, Fischer, sp., 1825, being the oldest, had been 

 adopted by De Koninck in 1841 for this specimen in lieu of Phillips' name of 



