108 Henry Woodtuard — On British Fossil Artkropoda. 



Assuming- it to be, like Jordan's Arthrojpleura armata, part of the 

 body-segment of some large paleeozoic Crustacean (such as Stijlonurus 

 Scoticiis,^ or that singular form named hjme PrcBarcturus gigas, from 

 the Old Eed Sandstone of Herefordshire),- it seems almost certain 

 that this fragment has no affinity whatever with Eurypterus. 



With regard to the remaining fragments referred by Mr. Salter to 

 Euryptenis mammatus (see Woodcut, Figs. 4, 5, 6, and 7), I am in no 

 little difficulty ; for here again Mr. Salter's description is borne out 

 by his woodcut figures, but not by the specimens themselves. 



For instance, he speaks of the peculiar "tear-drop" ornamenta- 

 tion along the hinder margin of the segments, such as is seen in 

 some fragments from the Devonian of Kiltorcan, Ireland, truly 

 referred to Euryptenis. But in Figs 4, 5, 6, and 7, these are really 

 cracks in the tissue, as correctly represented in the plate by Mr. 

 Griesbach, which accompanies my Monograph, and not raised tuber- 

 cular ornamentations thereon, as seen in the annexed woodcut (Figs. 

 4, 6, and 7). Mr, Salter himself says : 



" The remaining pieces are evidently parts of a great Crustacean, 

 and almost certainly belong to this one, for they have the same 

 ornaments on the hinder edge ; but they differ remarkably by having 

 a curious set of short, wavy, interrupted ridges (or furrows, it is 

 impossible to say which) lying transversely to the length, and which 

 are equally distributed over the whole segment. They are not all 

 of the same size, small rounded ridges being mixed with those of 

 a more linear shape." 



I carefully studied these fragments, and also submitted them to 

 the examination of my colleague, Mr. William Carruthers, F.E.S., 

 who has devoted himself specially to the study of fossil plant- 

 remains, hoping that he would accept them as jDarts of some plant, 

 like Calamites or Knorria ; but for some time he was unable to do 

 so. I was therefore obliged to treat them as animal, and probably 

 Crustacean, although I could not compare them (like Figs. 2 and 3) 

 with any other form belonging to the order ; for the scale-like orna- 

 mentation so characteristic of Pterygotus and Eurypterus is altogether 

 wanting, nor could I detect any evidence of spines such as are 

 preserved on Fig. 2. 



Fortunately at this juncture a portion of an undoubted plant- 

 stem, from the Ironstone of the English Coal-measures, which Mr. 

 Carruthers had laid aside for examination, turned up, and furnishes 

 evidence of markings identical with those exhibited on Figs. 4, 6, 6, 

 and 7, so that there is no longer any reason to doubt their vegetable 

 origin. Mr. Carruthers has very kindly drawn up an account of 

 these remains, which accompanies my Monograph, so that they may 

 now be considered as disposed of in a satisfactory manner.^ 



1 See Pal. Soc. Mon. Merostomata, part iv., and pi. xxii. and xxiii. 



2 Trans. Woolhope Naturalists' Field Club, 1870, p. 266. 'Fossil Sketches,' 

 No. 9, figs. 1 and 2, and No. 10. 



2 This account, together with some further observations, which Mr. Carruthers has 

 kindly promised to furnish, will appear in the April Number of the Geological 

 Magazine. — Edit. Geol. Mag. 



