F. B. Cowper Reed — Trilobites, Haverfordwest. 103 



LiCHAs (Mbtopolichas) laoiniatus, Dalman (?). 



There is one specimen of a pygidium probably referable to this 

 species from the Slade Beds exposed at the roadside a few hundred 

 yards west of St. Martin's Cemetery, Haverfordwest, in Mr. Turnbull's 

 collection. Though this specimen is not well preserved, the more 

 elongated form distinguishes it from L. affinis. L. laciniatus has 

 been described from the Bala of the Lake District ^ and other British 

 localities. 



LiCHAs (Platylichas) margaritifek, Nieszkowski, var. 



Some fragments of head-shields of a species of LicJias were 

 collected by Messrs. Marr & Roberts from the Slade Beds of Eobeston 

 Wathen and Ben Lomond Cottage, Haverfordwest, but no specific 

 identification was given. Portions with similar characters from 

 the same horizon occur in Mr. Turnbull's collection. They must 

 undoubtedly be referred to that section of the genus which has been 

 designated Platylichas,"^ and they are almost indistinguishable 

 from L. margaritifer, Nieszk.,^ of the Baltic provinces, to which 

 a form from the Chair of Kildare Limestone has also been 

 referred. The median lobe of the glabella and the bicomposite 

 lateral lobes have the typical shape and definition of this species ; 

 the axial furrows are likewise quite obsolete posteriorly, the 

 fixed cheeks and the fourth lateral lobes being completely fused 

 and forming a gently convex surface, marked off from the median 

 lobe by the additional furrow which connects the base of the 

 bicomposite lobes with the occipital furrow ; there is the usual 

 pair of small rhomboidal occipital lobes; and the eye-lobe and 

 furrow are well seen. The surface seems to be finely tuberculated 

 rather than granulated ; and there is a median tubercle on the 

 neck-ring in one of the specimens, which is apparently absent in 

 the Eussian examples. 



Family CHEIRURID^. 



Cheikurus (s.g. PsEUDosPH^RExocHus) aff. suBQTJADRATUs, Reed. 



The subgenus Pseiidospli(erexochus has been recorded by the 

 author* from the Keisley Limestone, and its relations have been 

 discussed in another place. ^ Its presence in the Haverfordwest 

 area has now to be recorded, specimens of head-shields showing 

 the typical features, but not well enough preserved for precise 

 specific identification, occurring in the Slade Beds of Upper Slade 

 in Mr. Turnbull's collection. The form appears to resemble 

 Ps. subquadratus of the Keisley Limestone very closely. 



1 McCoy: Synops. Brit. Pal. Foss. Woodw. Mus., p. 150, pi. IF, fig. 17 

 (J. subpropinqua) . 



2 Eeed: Q.J.G.S., toI. Iviii (1902), p. 72. 



3 Nieszkowski, Mon. Trilob. Ostseeprov. : ArcMv. Liv.-Est-Kurland, ser. i (1857), 

 p. 568, t. i, fig. 15. 



* Eeed: QJ.G.S., vol. lii (1896), p. 421, pi. xx, figs. 10, 11. 

 5 Eeed: Geol. Mag., Dec. IV, Vol. Ill (1896), pp. 117, 161. 



