Mr. D. Sharpe and Mr. Salter on Fossils from South Africa. 229 



Fig. 2. Under-side of the head of another specimen ; the crust lost : the rostral shield, with 

 the projecting tubercle, and the suture along the margin of the cheek, are well seen 

 here: the suture is visible also in fig. lb. From Leo Hoek. 

 Fig. 3. Outline of the head of a very large specimen. This variety has spines on the lower 



glabella-lobes. From the Warm Bokkeveld. 

 Fig. 4. Entire body and tail of a specimen with but few tubercles. From Gydow Pass. 

 Fig. 5. Two segments of the body of a many-spined variety. From Gydow Pass. 

 Fig. 6. A segment broader, in proportion to the width, than usual, and trilobed further inward ; 



probably belonging to a distinct species. From the Warm Bokkeveld. 

 Fig. 7 «• A fine tail of a moderately spiny variety. From Leo Hoek. 

 7 A. A side view of the same, showing the large facet. 

 7 c. The incurved under portion of the tail. 

 7 c?. A portion of the surface, magnified. 

 Fig. 8. The tail of a young individual ; without spines. From Gydow Pass. 



Plate XXV. 



Fig. 1. Phacops Africanus, Salter; p. 218: a specimen of the largest size, with the crust 



removed. From Gydow Pass. 

 Fig. 2. Body and tail of another specimen ; the axis is rather depressed, so as to appear 



broader than it really is. From Gydow Pass. 

 Fig. 3. Segments of a specimen, with dorsal spines on each segment. From Hottentot's Kloof 

 Fig. 4. Tail of the same species. From Hottentot's Kloof. 



Fig. 5. Head of the same species; showing the elevated eye. From Gydow Pass. 

 Fig. 6. Head of the same species. Cedarberg. (Mus. Pract. Geology.) 



6 a. Seen from above. 6 b. Side view. 

 Fig. 7- Under-side of head of the same specimen. 



Fig. 8. A small head, showing the lateral spines very perfectly. From Gydow Pass. 

 Fig. 9. Body of an individual belonging to the same species. Cedarberg. (Mus. Pract. Geology.) 



9 a. Side view. 9 b. View of the caudal extremity. 



9 c. Some body-rings, with the curved and spinose pleurae. 



Fig. 10. Phacops Caffer, Salter, young, p. 219. Head. From Gydow Pass. 



10 a. Side view. 10 b. Seen from above. 



Fig. 11. The head of a much larger specimen. From Leo Hoek. 



Figs. 1 2 G & 1 2 6. The eye of the same specimen, magnified. 



Fig. 13. Nearly perfect specimen of the same species. From Gydow Pass. 



Fig. 14 a. Typhloniscus Bainii, Salter; p. 221. 



14 b. One of the body-segments, with the terminal spine [the latter is too long in the 

 drawing] . 

 Fig. 15. Tentaculites crotalinus, Salter; p. 222; nat. size. From the Warm Bokkeveld. 

 Fig. 16. External shell, magnified. 

 Fig. 17« Internal cast, magnified. 



Fig. 18. Portion of a variety, with more rings in the youngest portion; magnified. 

 Fig. 19 a. Serpulites Sica, Salter; p. 222. 



19 b. A specimen magnified. From the Warm Bokkeveld. 



