56 BRITISH PALEOZOIC PHYLLOCARIDA. 



broken, but probably ended originally in a neat angle at or near the dorsal margin. 

 The parallel striae are slightly raised on the remaining patches of the thin, smooth, 

 brown test. Striae sometimes one centimetre apart, but closer together towards 

 the ventral edge. Marginal rim strong. 



Another specimen (PI. VII, fig. 3), also from the Lower Ludlow series, evi- 

 dently belongs to the same species. It is the specimen M in the Oxford Museum 

 (G-rindrod Collection), and it is preserved in greenish-grey, micaceous, and calca- 

 reous mudstone. This suboblong carapace is broken at the ends, with the right 

 valve embedded. An imperfect thin film of the other, retaining a small patch of 

 fine longitudinal striae near the ventral margin in the hinder half, covers the obscure 

 subconvex mass representing the contents of the carapace. The anterior fracture 

 shows this little mass to contain some minute indefinite remains of organic parts, 

 like two vertical rows of roundish spots (? sections of limbs). 



The posterior fracture exhibits four of the body-segments, preserving their 

 smooth test, within the carapace and continuous with others still further in. 

 Outside the carapace are the penultimate and ultimate segments. The last segment 

 (6 mm. long) is marked with faint striae, slightly oblique from above downwards 

 and backwards. A style (about 12 mm.) and one stylet (7 mm.), both smooth and 

 rather broad or dagger-shaped, are attached by an indistinct articulation. 



We wish to associate this rare but distinct species of Ceratiocaris with the 

 name of our deceased friend Mr. J. W. Salter, who worked so long and so well on 

 these and allied Phyllopoda. 



24. Ceratiocaris laxa, T. B. J. 8f E. W., 1886. PL VIII, fig. 12 ; PI. X, fig. 12. 



1885. Ceiiatiocabis sttgia, T. R. J. & B. W. Third Eeport Palseoz. Phyll., 



p. 345; Geol. Mag., 1885, 

 p. 396. 



1886. — laxa, — Fourth Report, p. 231; Geol. 



Mag., 1886, p. 458. 



One of the specimens in the British Museum marked 59648, from Lesmahago, 

 is a small acute-ovate carapace (25x13 mm.), pointed in front, truncate behind, 

 with which is associated a complete, but somewhat crushed, body of thirteen or four- 

 teen segments, five (15 mm.) of which are external, and have appended to them a 

 neat trifid set of long, narrow, sharp appendages. The strongest is the telson, 

 delicately ridged, and 17 mm. long; and the others, about 8 mm. long, are the 

 stylets. 



This small and very delicate specimen (PI. VIII, fig. 12), in black shale, with a 

 small, thin, calcareous vein, from Lesmahago, exhibits on the anterior part of its 



