180 



BRITISH FOSSIL CRUSTACEA. 



The spot marked e on the annexed Woodcut (Fig. 70), near the latero-anterior border of 

 the raised glabella, probably indicates the position of the eye. There is a slight indication 

 of costas on the front border of the head. 



Formation and Locality. — Upper Ludlow, near Ludlow ; Mus. Pract. Geology, Jenny n 

 Street ; Lower Ludlow, Ledbury ; British Museum. 



Fig. 71. — Lip-plate of Pterygotus from the Upper Silurian; Rootzikiill, Isle of Oesel, Baltic; 

 associated with Pseudoniscus, JSxapinurus, and Bunodes. 1 



Postscript. — After the foregoing pages had gone to press, Mr. James Armstrong, 

 whilst visiting the British Museum, carefully examined the matrix in which the specimens 

 of Eurypterus Scoideri are contained (figured on Plates XXV, XXVI, and XXVII, and 

 stated to be from Burdie House, near Edinburgh), when he at once pronounced them 

 to be from a quarry at Kirkton, near Bathgate, West Lothian ; which is not in the Coal 

 proper but in the Carboniferous Limestone. This bed also contains Sp/ienopteris Hibberti 

 (described in vol. iii, p. 73, of Lindley and Hutton's ' Fossil Flora'). 



The Limestone is a freshwater deposit, and abounds in bands of silex alternating with 

 calcareous matter, and presents all the appearance of having been deposited by thermal 

 waters during the carboniferous epoch. — H. W. 



British Museum ; 17 th September, 1872. 



1 ' Archiv fur die Naturk. Liv- Ehst- und Kurlands,' Dorpat, 1859, Series 1, vol. ii, p. 382, pi. i, fig. 19. 



