110 TRILOBITES OF GIRVAN. 



length and the same in width. The rest of the head-shield is not preserved, but 

 the features of the glabella are sufficient to show that it belongs to the peculiar 

 section or sub-genus of Lichas known as Conolichas, 1 which has not hitherto been 

 recorded from Britain. 



Collection. — Mrs. Gray. 



Horizon and Locality. — Drummuck Group (U. Bala) : Starfish Bed, Thraive 

 Glen. 



12. Lichas, sp. ind. Plate XV, fig. 7. 



Description. — A minute head-shield, only 3 mm. long, from Balclatchie, shows 

 certain peculiar features. It is tumid, strongly convex from side to side and from 

 back to front. The glabella rises steeply from the neck-ring, and has a central 

 lobe which gradually and slowly expands towards the front, but does not much 

 overhang the lateral lobes, which are bicomposite, broadly oval, rounded at both 

 ends, as wide as the central lobe, and three fourths the total length of the glabella, 

 nearly reaching the neck-ring. They are completely circumscribed by furrows, 

 except at the base, and have a distinct notch on their inner side. The first lateral 

 furrows converge posteriorly at an angle of about 30°, are very slightly arched 

 inwards, bending outwards at their posterior end to terminate suddenly behind the 

 lateral lobes. The neck-furrow is well marked, and separates off a rounded 

 occipital segment. The specimen is not well enough preserved to show if the 

 fourth lateral lobes are defined, or if occipital lobes are present. A narrow, 

 flattened, smooth border surrounds the front end of the head; and a few large 

 scattered tubercles are visible on the glabella. 



Collection. — Mrs. Gray. 



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



Genus LICHAPYGE, Callaway. 

 1. Lichapyge? problematica, sp. nov. Plate XV, figs. 8 — 10. 



1880. Dionide ? sp. ind. c, Nicholson and Etheridge, Mon. Silur.Foss. Girvan, fasc. iii, p. 295, pi. xx, 

 fig. 4. 



Specific Characters. — Pygidium semi-elliptical to subquadrate, flattened. Axis 

 weakly convex, conical, about half the length of the pygidium and one third its 

 width at front end; consisting of 6 — 7 rings, of which only the first four are distinct 

 and bear a faint median tubercle. From the extremity of the axis extends a 



1 Reed, 'Quart. Journ. Geol. Soc.,' vol. lviii (1902), p. 78. 



