OF THE CULM OF DEVON. 69 



pentangular lobe with a slightly raised margin, and a rounded central depression, 

 the surface of which is striated. 



The head of P. minor appears to us to be very distinct from any of the species 

 of Carboniferous Trilobites hitherto figured, but the pygidium may be compared 

 with P. Mchivaldi (PI. IV, figs. 9 and 13); the axis, however, in P. minor tapers 

 more rapidly to a point. 



Formation. — Lower Culm. 



Locality. — Waddon-Barton, Devonshire. 



Figs. 6 and 7 are preserved in the British Museum (Natural History), and figs. 

 5 and 8 a are in the cabinet of Mr. J. E. Lee. 



30. Phillipsia Cliffoedi, H. Woodiv., sp. nov. PL X, figs. 8 b, 9, 10, 11, 12. 



The head of this species resembles that of P. Leei, but the cheek-spine is 

 much shorter, and the lateral furrows on the glabella are more marked. The 

 head is much distorted by cleavage, and its accurate description is attended with 

 some difficulty, the head being imperfect. Thoracic segments unknown, probably 

 nine in number. 



Pygidium. — We are fortunately able to figure five pygidia of this species 

 having well-marked characters of their own. The tail-shield is nearly twice as 

 broad as it is long, the axis is one-third of its breadth at the proximal border, but 

 rapidly diminishes to one-seventh at its bluntly -rounded extremity ; here the shield 

 is bordered by a wide margin covered with fine concentric striae (being an impres- 

 sion of the underside) ; the border is one seventh the length of the pygidium, but 

 diminishes in width laterally. The axis of the tail is composed of thirteen 

 coalesced rings or somites, and has ten lateral pleurae on each side ; these 

 bifurcate near their extremities as they approach the margin. There are no 

 puncta, spines, or tubercles observable on this species. 



The pygidium of Ph. Cliffordi agrees most in general facies with that of 

 Ph. Colei (Plate II), but in the former the pleurae are bifid at their extremities, 

 not simple as in the latter species. It may also be compared with Griff. Garring- 

 tonensis (PI. IX, figs. 6 a } b), but the Culm form is broader and shorter in 

 proportion. 



I have much pleasure in dedicating this species to Lord Clifford, of Ugbrook 

 Park, Devonshire, upon whose estate the Culm is well exposed. These Trilobites 

 were discovered by Mr. Lee on one of his lordship's farms at "Waddon-Barton, 

 and it was by his permission that Mr. Lee secured a quantity of the shale to break 

 up, resulting in the discovery of the specimens here figured. 



Formation. — Lower Culm-shale. 



