46 



PUOCEEDIKGS OP THE GEOLOGICAL SOCIETY. [DeC, 20, 



Analysis of the insohible silicate by Nordstrom : — 



From the largest Of rock attached to the 



blocks. outside of largest block. 



Silica .... 





:} 



D 



61-79 



23-31 



1-45 



2-83 '. 

 8-33 



2-29 



44-01 



Alumina 



Sesquioxide of Iron . 

 Protoxide of Iron . . . 

 Magnesia 



14-27 



3-89 



14-75 



... 8'11 



Lime 



Potash .... 

 Soda 





10-91 

 fO-97 

 |2-61 





100-00 



rscussiON, 



99-52 



Mr. Roberts protested against the evolution of gaseous matter 

 being considered a proof of meteoric origin. 



Prof. Ramsay reiterated his previously expressed opinion, that 

 the masses of iron might be of telluric origin . 



3. Further Remarlcs on the Relationship of the Xiphosura to tJie 

 Etjrypterida and to the Trilobita and Arachi^ida. By Henry 

 Woodward, Esq., P.G.S., F.Z.S. 



I HAD, on a former occasion (November 21, 1866), the honour to 

 communicate a paper to this Society " On some points in the struc- 

 ture of the Xiphosura having reference to their relationship with the 

 Eurypterida "*, in which were discussed the grounds for the union 

 of these two suborders (afterwards dealt with in greater detail in 

 the monograph of the Merostomata in the Palseontographical So- 

 ciety's publications for 1866). I therefore venture to think it may 

 not be considered inappropriate if I bring the subject again under 

 your consideration after an interval of five years, during which time 

 some considerable additions have been made to our knowledge of 

 this group. 



The papers to which I shall have occasion especially to refer are 

 the following : — 



1. " On a Xew Limuloid Crustacean {Neolimidus falcntus) from 

 the Upper Silurian of Lesmahagow, Lanarkshire." By H, Wood- 

 ward. (GeoL Mag. 1868, vol. v. pi. i. fig. 1, p. 1.) 



2. " On some new Species of Crustacea from the Upper Silurian 

 Rocks of Lanarkshire, and further Observations on the Structure of 

 Pte?^ygotus" By H. Woodward, (Quart. Journ. Geol. Soc. 1868, 

 vol. xxiv. pis. ix. & x., p. 289.) 



3. "Notes on some Specimens of Lower Silurian Trilobites." By 

 E. Billings, E.G.S. (Quart. Journ. Geol. Soc. 1870, vol. xxvi. pis. 

 xxi. & xxii., p. 479.) 



4. " Note on the Palpus and other Appendages of Asaphus from 



* Quart. Joiirn. Geol. Soc. 1867, vol. xxiii. p. 28. 



