ON THE FOSSIL PHYLLOPODA OF THE PALHOZOIC ROCKS, 343 
it is quite reversed—that is, lying at the anterior instead of the posterior 
end, as described by Mr. Salter (‘ Siluria,’ 1867, p. 236, &c.). 
The specimen Cambridge Mus. 0/135 has the rostrum lying at an 
angle across the anterior extremity. 
Of CO. papilio, good specimens from Lesmahago :— 
Cambridge Mus., 6/135. M. P. G. x44, x 3h. 
Brit. Mus. 41894, 41895, 41896, 41897, 45161, 47989, 58669. 
We have seen also some fossil carapaces from Benson Knot, Kendal 
(Upper Ludlow) which agree perfectly in form and proportions with 
U. papilio from Lesmahago, also in ornament, except that the postero- 
dorsal convergence of the striz is not present. These are Brit. Mus. 
some of those marked ‘44342’; M. P. G. x1 (‘Catal.’ 1878, p. 141); 
and Cambridge Mus. 6/35. They range from 65 mm. long and 32 mm. 
high to 75x40mm. Also a large imperfect specimen and some frag- 
ments in brown shale from Linburn, near Muirkirk (Brit. Mus., all 
marked ‘58878’). The specimen b/35 is included in O. inornata, M‘Coy, 
by Mr. Salter, ‘Catal. C. S. Foss.’ 1873, p. 177. 
Moreover, the specimen N in the Ludlow Museum has the pro- 
portions and appearance of C. papilio, as far as it is preserved (wanting 
the antero-dorsal angle), from Church Hill, Leintwardine.! 
4, CERATIOCARIS sTyGiA, Salter. 
1859. Ceratiocaris, Salter. In Murchison’s ‘ Siluria,’ 2nd (3rd) ed. p. 262, wood- 
cut fig. 2. 
1860. Ceratiocaris stygius, Salter. ‘Ann. Mag. Nat. Hist.’ ser. 3, vol. v. p. 154, wood- 
cut figs. 2, 3 (fig. 1 is C. papilio). 
1865. Ceratiocaris papilio, Salter and Woodward. ‘Cat. and Chart Foss. Crust.’ 
p. 17, fig. 5. 
1867. Ceratiocaris stygius, Salter. In ‘Siluria,’ 3rd (4th) ed. p. 236, woodcut fig. 2, 
and p. 517. 
1873. Ceratiocaris stygius, Salter. ‘Cat. Camb. Sil. Foss.’ p. 178. 
1873. % 9 R. Etheridge, jun. ‘ Mem. Geol. Surv. Scotl. Expl. Map 23,’ 
pp. 55, 56. 
1876. Ceratiocaris papilio, F. Roem, ‘ Leth. geogn.’ Th. i. ‘ Leth. pal,’ pl. 19, fig. 4. 
1876. = stygvus, Armstrong and others. ‘Cat. W.-Scot. Fossils,’ p. 24. 
1877. 3 as H. Woodward. ‘Catal. Brit. Foss. Crust.’ p. 73. 
1878. Bg A Huxley and Etheridge. ‘Cat. Camb. Sil. Fossils,’ p. 142. 
Carapace-valves trapezoidal; back straight, but curving down for 
a short distance to the mucronate dorsal angle of the anterior edge, 
which then slopes, with a slight convexity and at a sharp angle, down- 
wards and backwards, to about the middle of the ventral margin, where 
the valve is deepest (highest) ; the other half of the ventral edge rises 
slowly with a straight or nearly straight oblique edge to the blunt 
postero-ventral corner, whence the truncate hind margin rises, with a 
gentle concave curve, to the sharp postero-dorsal angle. When the 
valves are spread open a triangular space is left between the antero- 
dorsal angles. This condition and the shape are well shown in the 
specimen M. P.G. x 4;. The outline is often modified by pressure in 
‘ The very rich localities for these Silurian Phyllopods in the neighbourhood of 
LIndlow are enumerated and described in the Rev. J. D. La Touche’s ‘ Handbook of 
the Geology of Shropshire, 1884,’ pp- 26, 27, especially Ludford Lane, Bow Bridge, 
Leintwardine, Church Hill, and Trippleton Farm. See also the Rev. W. S. Symonds’ 
“Record of the Rocks,’ 1872, p. 194, &c. for notices of Ludlow and its environs from 
a geologist’s point of view. 
