in the Culm-shales of Devonshire. 541 



Phillipsia Leei, H. Woodw. 1884. PL XVI. Figs. 6 and 7.' 

 Fhillipsia Leei, H. Woodw. Pal. See. Mon. Carb. Trilob. part ii. 1884, p. 67, 

 pi. X. fig. 1, 2, 3, and 4. 



This is one of the largest of the Guhn 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 some- 

 what strongly arched, and is widest in the centre; the facial suture 

 separating the free-cheek ci'osses the neck-lobe obliquely along its 

 pleural portion close to the axal furrow ; a deep furrow circumscribes 

 the boi'der 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. 



Thoracic segments. — The axis of the thorax is somewhat wider 

 than its pleuras, 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 pleurEe 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 

 afSnities with P. gemmulifera, P. truncatula and P. Eichwaldi ; 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 P. Leei are exceedingly small, 

 whereas in the other species of Phillipsia they are very large and 

 prominent. 



P. Leei differs from P. Colei in possessing cheek-spines. The 

 pygidium of P. 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 Ph. Leei with Proetus posthiimus of Eichter, 

 (Zeitsch. Deutsch. Geolog. Gesells. 1864, bd. xvi. p. 160, taf. iii. 



1 See explanation of PI. XVI. Geol. Mag., Nov 1884, p. 489. 



