U BRITISH PALEOZOIC PHYLLOCARIDA. 



its middle. Oxford Mus. E. " Lower Ludlow ; Leintwardine." Brownish mud- 

 stone. 



PL V, fig. 4. Four segments and two of the appendages. The four body-seg- 

 ments, with relics of the test, are ornamented with longitudinal and anastomosing 

 wrinklets. The style and one stylet, imperfectly preserved, are both longitudinally 

 ridged. The head of the telson (style), adherent at the joint to the ultimate segment, 

 is lattice-marked ; and the telson is dorsally pitted. The stylet, almost perfect, 

 was probably about 20 mm. in length, and the style may have been about 40 mm. 



In light grey mudstone ; slightly calcareous. Lower Ludlow ; Church Hill, 

 Leintwardine. Marston Coll. Ludlow Museum, L. Figured in La Touche's 

 1 Handbook of the Geology of Shropshire,' 1884, pi. 17, fig. 565. 



PI. IX, fig. 4. Imperfect segment. A portion of an abdominal segment 

 showing the epimeral furrow and the longitudinal, inosculating, raised striae or 

 wrinklets, turning down at the lower corner of the anterior portion. The upper 

 anterior corner is wanting. Magnified 4 diameters. This seems to agree with the 

 small specimen of G. tyrannus, PI. Ill, fig. 5. Compare also PL V, figs. 4 and 

 6 6; PI. IV, fig. 4 ; and PL I, aa. Some of these are in reverse, as they belong 

 to the other side of the abdomen. In Mr. Salwey's collection, Ludlow ; on the 

 back of the specimen with Physoca/ris vesica (PL VII, fig. 8) ; from Leintwardine. 



In the Ludlow Museum the specimen marked M, from the Lower Ludlow-beds 

 of Clunbury (?), has four segments of G. tyrannus, with appendages, all crushed. 

 Also the specimen Q, from Church Hill, Leintwardine, Lightbody Coll., seems to 

 belong to the same species, showing part of the last segment and appendages. 



5. Ceeatiooaris giqas, Salter, MS., 1865. PL III, fig. 1 ; PL IV, fig. 2 ; 



PL V, fig. 5. 



1865. Ceeatiocaris gigas (Salter), H. & E. Catal. Foss. M. P. G., p. 79. 

 1878. — — — H.N.Sf E. Catal. Cambr. and Silur. Fossils, 



Mus. Pract. Geo!., p. 141. 



1885. — Murchisoni, T. B. J. & H. W. Third Keport, Brit. Assoc, 



p. 338 ; Geol. Mag., 1885, 

 p. 389. 



1886. — gigas, — Fourth Eep., Brit. Assoc, 



pp. 229,230; Geol. Mag., 

 1886, p. 456. 



The caudal appendages of G. Murchisoni have a slight curvature; there are 

 others much like them, but straight and associated with a large ultimate segment, 



