66 CARBONIFEROUS TRILOBITES 



28. Phillipsia Leei, K Woodw., sp. nov. PI. X, figs. 1, 2, 3, and 4. 



This is one of the largest of the Culm Trilobites, and is represented by- 

 numerous specimens. 



The head-shield is semicircular in outline, the glabella occupying about one- 

 third of its breadth at the widest part of the head, the glabella is moderately 

 elevated, and is surrounded by the flattened border of the fixed cheek, which 

 expands in front, forming a flat and somewhat broad semicircular border around 

 the anterior portion of the glabella. Two small basal lobes are seen one on either 

 side near the posterior margin of the glabella, and two short oblique furrows mark 

 its sides. The neck-lobe is well defined and somewhat strongly arched, and is 

 widest in the centre ; the facial suture separating the free-cheek crosses the neck- 

 lobe obliquely along its pleural portion close to the axal furrow ; a deep furrow 

 circumscribes the border and separates the raised inner portion of the free-cheek 

 from the flattened margin of the shield which in its decorticated condition is seen 

 to be ornamented by parallel lines. The angles of the head-shield are produced 

 into strong rather broad spines about two-thirds as long as the head. The eyes 

 are very small, semilunar, and often quite obliterated by compression. 



TJwracic segments. — The axis of the thorax is somewhat wider than its pleurae, 

 the separate segments are distinctly marked by deep furrows, each of the pleurae 

 being marked by a central groove ; their extremities are rounded ; the thoracic 

 segments were probably nine in number, but the whole number cannot be seen in 

 any one specimen. 



The pygidium is one-fifth broader than long, the axis forms one-third of its 

 breadth at the proximal border, but diminishes very rapidly, terminating in a 

 somewhat blunt point near the posterior margin. 



There appear to be about fourteen coalesced segments in the axis of the 

 pygidium represented by about nine grooved pleurae on each side, surrounded by a 

 narrow smooth border. 



This species, which we have dedicated to the discoverer, Mr. John Edward Lee, 

 F.S.A., F.G.S., of Villa Syracusa, Torquay, presents affinities with Ph. gemmulifera, 

 Ph. truncatula and Ph. Eichivaldi, in all these species the angles of the head-shields 

 are produced into lateral spines, and the flattened border of the glabella encircles 

 the raised central portion, but the eyes in Ph. Leei are exceedingly small, whereas 

 in all the other species of Phillipsia they are very large and prominent. 



Ph. Leei differs from Ph. Colei in possessing cheek-spines. The pygidium of 

 Ph. Leei is also distinct, being narrower and more pointed in its axis ; the tail- 

 shield itself is also more triangular in outline. 



We have compared Phillipsia Leei with Proetus posthumus of Richter 1 to 

 1 ' Zeitsch. Deutsch. geolog. Gesells.,' 18G4, Bd. xvi, p. 160, Taf. iii, fig. 1. 



