326 Intelligence and Miscellaneous Articles. 



Shotts, Lanarkshire. (2) The Macrurous Crustacean of which an 

 imperfect specimen was figured in Mr. Prestwich's memoir on the 

 Coalbrook Dale Coal-field (plate 41, fig. 9, Apus dubius) : this is 

 referred to a subgenus (Palteocarabus) of the genus Anthrapalcemon ; 

 and another specimen from Ridgeacre Colliery was referred to. 



(3) A specimen from the Carboniferous Limestone of Derbyshire. 



(4) A small Crustacean, from the Mountain-limestone of Fifeshire, 

 figured and described by the author in the ' Transactions of the Royal 

 Society of Edinburgh,' vol. xxii. p. 394, as Uronectes sockdis, but 

 now regarded by him as belonging to the Macrura. 



XLI. Intelligence and Miscellaneous Articles. 



ANALYSIS OF GYROLITE. BY HENRY HOW, PROFESSOR OF CHE- 

 MISTRY, KING'S COLLEGE, WINDSOR, NOVA SCOTIA. 



HT HE mineral gyrolite was first described by Professor Anderson 

 -*- of Glasgow* as a new species from the Isle of Skye ; it is 

 stated by Greg and Lettsomf to occur without doubt at two loca- 

 lities in Greenland, and, according to Heddle, at Faroe. The only 

 other notice of it that I am acquainted with is by L. SaemannJ, who 

 mentions that he examined a specimen, no locality being given, 

 mixed or interlaminated with pectolite, and suggests that this mi- 

 neral losing its alkali becomes gyrolite, and losing its lime becomes 

 Okenite. No other analysis than the original one of Professor 

 Anderson has, I believe, been published ; the following account of 

 its occurrence among the minerals of Nova Scotia shows it in such 

 association as affords a mode of explaining its origin by change in 

 apophyllite : — I met with it in Anapolis County, N. S., some twenty- 

 five miles south-west of Cape Blomidon, between Margaretville and 

 Port George, on the surface of fractured crystalline apophyllite ; and 

 on further breaking the mass a good many spherical concretions of 

 pearly lustrous plates were observed in the interior, of sizes varying 

 from that of a pin's head to nearly half an inch in diameter : their 

 outline was well defined, and the external characters as given by 

 Anderson were recognized on examination ; it afforded the following 

 results on analysis : — The mineral was ignited for water, and the 

 residue treated with HC1 ; the resulting dried silica was weighed, and 

 then fused with carbonated alkali ; and the weight of the small quan- 

 tities of alumina, &c. so separated was deducted from that of the 

 first silica. I place my numbers by the side of those of Anderson, 

 and give the calculated per-centages for his formula : — 

 How. Anderson. 



Potassa . . 



. 1-60 







Magnesia 



. 0-08 



0-18 



Calculation. 





1-27 



T48 



A 



Lime . . . 



. 29-95 



33-24 



32-26 2CaO =56 



Silica . . . 



. 51-90 



50-70 



52-18 2Si0 9 = 90-6 



Water . . 



. 15-05 



14-18 



15-55 3HO =27-0 



99-85 99-78 99-99 173G 



* Trans. Roy. Soc. Edinb., and Phil. Mag. Feb. 1851. 

 t Manual of Mineralogy, p. 217. 

 X First Supp. to Dana's Mineralogy, p. 9, 



