New Eur If pter id from U'p'pcr Coal-measures of Radstoch. 439 



plete specimens of Eurypterus, Slimonia, StylonuruSy and 

 Pterygohts have been obtained and carefully studied. It is 

 not so, however, with the Eurypterid remains interred in our 

 carboniferous rocks, for though minute fragments of their 

 coatings, showing the characteristic sculpturing, have been 

 brought to light from almost every horizon of that formation 

 in Scotland, and more especially from the beds which repre- 

 sent its old land surfaces, yet the hitherto described speci- 

 mens may almost be counted on the fingers of one hand.^ 

 It is therefore highly gratifying to obtain a specimen of the 

 cephalo-thoracic shield of an Eurypterid, in an almost perfect 

 state of preservation, from the highest Coal-measures of 

 England. For the opportunity of studying the specimen, 

 and bringing the results before this Society, I am indebted 

 to my friend Eobert Kidston, who has so ably worked out 

 the flora of the Eadstock coalfield. 



Description of Specimen. 



The cephalo-thoracic shield, or carapace, is semi-ovoid, 

 the posterior margin along which it was attached to the 

 trunk being arcuate. The carapace is arched and tumid, 

 and diversified by several areas of elevation and depression. 

 A mesial depression passes from the posterior to near the 

 anterior margin, and two shorter depressions run more or 

 less parallel to it, one on each side, separating the cheeks 

 from two raised areas on the back. Two further depressions 

 cross the path of these obliquely, and pass inwards from the 

 lateral margins, a little in advance of the postero-lateral 

 angles, and meet in the median groove, near the posterior 

 margin. Nearly half-way from each end of the median 

 groove rises a small elongated eminence, bearing the simple 

 larval eyes or ocelli, which are oval and about 1 mm. in 

 longest diameter, and separated from each other by an 



^ Mr James Bennie, who has for several years been continuing his researches 

 into the old land surfaces of the carboniferous strata of Scotland, mainly with 

 the purpose of searching for Lycopodraceous spores, finds fragments of Euiyp- 

 terus and Scorpion in more or less profusion in many coal seams and "dirt- 

 beds," especially from the lower carboniferous strata, which he has more 

 particularly studied. 



VOL. IX. 2 G 



