﻿PLATE VII. 



UPPER SILURIAN (WENLOCK). 



Figs. I — 12. Deiphon Forbesii, Barrande. All the principal specimens known. 



1- ,, ,, The most perfect specimen extant ; natural size and magnified. It is in the 



rich cahinet of my friend Dr. Grindrod, of Malvern, and shows the eyes, 

 pleurae, and tail, to perfection. Malvern Tunnel. 



2. ,, ,, A younger, but nearly perfect, example. Same locality and cabinet. 



3. „ ,, From Mr. C. Ketley's collection. Same locality. 



4. ,, ,, Young head, from the late Mr. Mushen's collection. Dudley. 



5. ,, „ Somewhat older. Dudley. (Mr. Mushen's cabinet.) 



6*. ,, ., Largest head known. (Mr. Mushen's collection.) 6 a. Front view. 6" b. 



Side view. Dudley. 



7. ,. ,, Portion of glabella, magnified. 



8. „ ., Side view of perfect eye and free cheek ; from fig. 1. 



9. „ ,, Showing the supporting folds of the eye (the lentiferous surface lost) from 



fig. 5. This specimen also shows the curious blunt process on the forward 

 edge of the head spine. 



10 a. „ ,, Mr. Ketley's specimen, showing hypostome and labrum, and the underside 



of the first six pleurae ; a beautiful specimen, which also shows the eyes in 

 place. 10 b. The same, enlarged. 10 c. Is a magnified front view of the 

 labrum ; 1 d, side view of ditto. From Malvern Tunnel. 



11. ,, ,, Tail, and part of the tenth body-segment. Dudley. (Woodwardian Museum.) 



12. ,, ,, Do., enlarged to twice its size. (Mr. Mushen.) Dudley. 



Figs. 13 — 20. Staurocephalus Ifurchisoni, Barr. 



13 a. ,, A Dudley specimen, from Mr. E. Hollier's cabinet, magnified. 



13 6. „ Side view of another. (Same cabinet.) Dudley. 



14. ,. Coiled specimen. (British Museum.) Natural size. 



IS a. „ Do. a fine example from Dr. Grindrod's cabinet: Wenlock Shale, Malvern. 



a. Natural size. b. Magnified. 



16. ,, Do., showing the border-spines to the head. (Same cabinet.) 



17. Fragment with the frontal crest of tubercles and the blunt labrum. 



(British Museum.) 



18. „ Middle and last body-segments, and tail; from the Decades of the 

 ( Survey ; partly restored, and magnified. 



LOWER SILURIAN. — CARADOC. 



19. Staurocephalus Mvrchisoni. Small specimen, figured by M'Coy, and in the Woodwardian 



Museum. Rhiwlas, Bala, N. Wales. 



20 a. „ ,, Do. (In Mus. Pract. Geology.) Same locality ; 20 b, en- 



larged. 



Fig. 21. „ globiceps, Portlock. The original specimen figured in Portlock's work 



and in Decade 11, Geol. Survey, a. Natural size; b, enlarged; 

 the tail is broken off at the apex. Tyrone. 

 Figs. 22 — 24. „ unicns, Thomson. A series of fine specimens from Professor Wyville 



Thomson's cabinet. Others are in the Museum Pract. Geology. 

 Girvan, Ayrshire. 



22 a. „ ,, The same head, front view, nat. size ; b, viewed sideways, c. Fig. 



22 a magnified ; it shows the gibbous glabella, forward eyes, 

 and minute free cheeks. 

 23, 24. ,, „ Body and tail. Nat. size, same locality. 



Fig. 25. „ sp. (St. nodulosus, MS., Salter), Professor Thomson's cabinet. This 



shows many differences from St. unicus, but is not sufficiently 

 preserved for me to be quite sure of its distinctness from 

 St. globiceps. Girvan, Ayrshire. 



