174 BRITISH FOSSIL CRUSTACEA. 



in our classification. The reasons may briefly be stated : — (1) We know of no undoubted 

 Eurypterus with body-segments ornamented with spines or tubercles like those of E. ferox. 

 (2) The segments, when seen in series, are never (in Eurypterus) of a uniform size, but 

 invariably diminish, as regards their breadth, from the seventh segment towards the 

 telson. With the single exception of Eurypterus Scouleri (a most aberrant form of the 

 Eurypteria), all the members have the segments but very slightly arched, and (save in 

 the three most posterior segments) always much broader than long. 



We may therefore consider Mr. Salter's Eurypterus ? ferox as excluded from the genus 

 Eurypterus, and also from Jordan's genus Arthropleura, and may refer it with considerable 

 confidence to Messrs. Meek and Worthen's Myriapodous genus Euphoberia. 



Formation. — Coal-measures. Clay-ironstone. 



Localities. — Coalbroak Dale, Shropshire ; Tipton, Staffordshire. 



Foreign Localities. — Coal-measures, Grundy, County Illinois, U.S. America. 



Genus 5. — Hemiaspis : — H. Woodw. 1865. 

 Species 1. -HEMIASPIS LIMULOIDES :— H. Woodw. PL XXX, figs. 1, 2. 



Hemiaspis limuloides, //. Woodward. Brit. Assoc. Report, Bath Meeting, 1864, 



Section C. 

 — — H. Woodward. Quart. Journ. Geol. Soc, 1864, vol. xxi, 



p. 490, pi. xiv, figs, la, 7 c. 



When I first drew attention to this genus at the Bath Meeting of the British 

 Association in 1864, only one nearly perfect specimen was known. 



Mr. Salter was acquainted with it, however, so long ago as 1857, and referred to this 

 individual, among other new and undescribed Crustacea, in a paper " On some New 

 Palasozoic Star-fishes " found at Leintwardine, Shropshire, 1 under the name of Limuloides. 



Portions of several others had also been met with, to which Mr. Salter attached MS- 

 names in the Museum of Practical Geology, Jermyn Street, but they have not been 

 heretofore described. 



The most perfect of these Limuloid forms was described by me in a paper read before 

 the Geological Society in June, 1865. 2 



1 See 'Ann. and Mag. Nat. Hist.,' 2nd series, 1857, vol. xx, p. 321. 



2 See ' Quart. Journ. Geol. Soc.,' 1865, vol. xxi, p. 490, pi. xiv, fig. 7. 



