LICHAS (CONOLICHAS) vEQUILOBA. 109 



Horizons and Localities. — Stinchar Limestone Group (Llandeilo) : Craighead. 

 ? Balclatchie Group (Llandeilo) : Balclatchie. 



10. Lichas (Amphilichas) sp. ind. Plate XV, figs. 4, 5. 



Remarks. — There are some fragments of a large head- shield from Dow Hill 

 which, though belonging to the same group and sub-genus as L. hibernicus, 

 are probably specifically distinct. The long bicomposite lobes converge more 

 inwards posteriorly, so that the neck of the median lobe has not its sides so 

 nearly parallel. Moreover, the first lateral furrows, in addition to their more 

 marked convergence, are not continued back to the neck-ring with uniform strength, 

 but almost die out a little behind the middle of the lateral lobes, being represented 

 posteriorly by only faint and shallow depressions on the surface. The occipital 

 segment and the other features appear to be identical with L. hibernicus. 



A portion of a very strongly tuberculated thoracic segment with the pleura 

 showing a somewhat irregular diagonal furrow, behind which lie some 2 — 3 

 specially large, rounded, prominent tubercles, elevated above the general tuber- 

 culated surface, may belong to the same species. 



L. Isevis, Eichwald, 1 is a species belonging to Amphilichas which has similar 

 incomplete first lateral furrows ; but I know of no other allied species. 



Collection. — Mrs. Gray. 



Horizon and Locality. — Balclatchie Group (Llandeilo) : Dow Hill. 



11. Lichas (Conolichas) cf. aequiloba, Steinhardt, 1874. Plate XV, fig. 6. 



1874. Lichas xquiloba, Steinhardt, Preuss. Geschieb. Gefund. Trilob., p. 31, pi. iii, fig. 6. 



1877. Conolichas ivquiloba, Dames, Zeitschr. deutsch. geol. Gesell., p. 807, pi. xiii, fig. 5. 



1886. Lichas sequiloba, Schmidt, Eev. Ostbalt. Silur. Trilob., pt. ii, p. 89, pi. v, figs. 4 — 10. 



1890. Lichas sequiloba, Pompecki, Trilobitf. Ost.-West. Preuss. Diluv. Geschieb., p. 48, pi. v, fig. 14. 



1901. Lichas xquiloba, G-iirich, Neues Jahrb. f. Miu., Beil. Bd. xiv, p. 519. 



1902. Lichas (Conolichas) lequiloba, Eeed, Quart. Jouru. Geol. Soc, vol. lviii, pp. 61, 79, figs. 15 a, b. 



Remarks. — There is one small incomplete head-shield from the Starfish bed in 

 Mrs. Gray's collection which shows the peculiar features of L. sequiloba, Steinh. 

 {op. cit.), so far as it is preserved. There is the characteristic suddenly swollen 

 and elevated anterior portion of the central lobe of the glabella wit h the long, 

 narrow, depressed neck between the elongated, oval, tricomposite lobes. The 

 whole glabella is coarsely but scantily tuberculated; it measures only 4 mm. in 



1 Schmidt, op. cit., p. 49, pi. vi, figs. 5—10. 



