354 Miscellaneous Intelligence. 



diseased beach-tree, many hectogrammes (each ahove 3 J ounces) 

 being collected with facility. This lichen, when pulverised and 

 sifted, appeared as a white earthy powder : 100 parts, by drying, 

 lost 5 parts. Being boiled with a solution of 100 parts of crystal- 

 lized carbonate of soda, and filtered through a cloth, the solution 

 was collected, and saturated by nitric acid, which caused no 

 effervescence. Acetate of lead being adderl, a dense white pre- 

 cipitate fell, and this, washed and decomposed by sulphuric acid, 

 gave a solution almost colourless, which, by crystallization, fur- 

 nished fine crystals of oxalic acid, amounting to 15-^ parts, not- 

 withstanding loss of matter. The residue left by the carbonate 

 of soda effervesced rapidly with muriatic acid, though previously 

 it suffered no change ; removing in this way the carbonate of 

 lime, the residue was again treated with carbonate of soda, and 

 by the second operation, furnished 8 parts more of crystallized 

 oxalic acid, and still oxalate of lime was left undecomposed. 



One hundred parts of the pulverised lichen, with 33 parts of 

 sulphuric acid, and a sufficient quantity of water, were boiled for 

 half an hour, filtered to separate the sulphate of lime, and the 

 liquid collected very carefully evaporated, to avoid re-action of 

 the excess of sulphuric acid on the oxalic acid. When cold, the 

 Avhole became crystalline, and by pressure in bibulous paper, 

 17 parts of yellowish-v/hite oxalic acid were obtained, some still 

 remaining dissolved. 



About the same quantity of oxalate of lime was found in the 

 following lichens, perfwsana communis^ wee olaria scrvposa^isidium 

 corallinum^ patellaria tartarea, — ventosa-rubra^ — hemaiomma, bceo- 

 myces ericetorum — squamaria lentigera^'placodium radiosum, — ochro- 

 leucum, psora Candida. The oxalate of lime is to these and ana- 

 logous cryptogamous plants what carbonate of lime is to coral- 

 lines, and phosphate of lime to the bony structure of more 

 perfect animals. The oxalate of lime diminishes progressively in 

 the family of lichens, as the species lose their crustaceous granu- 

 lar contexture, and acquire a foliated membranaceous or carti- 

 laginous aspect; but the latter always retain a remarkable 

 quantity. 



Hence it will appear that the crustaceous lichens are an abund- 

 ant source of oxalic acid, from which it may be obtained at low 

 price. The common variolaire is found on almost all old and 

 feeble beech trees, in the bark of which it is implanted, forming 

 large white rough crusts, of variable thickness, which may 

 easily be scraped off. 



It will not be observed without interest, observes M. Bracon- 

 not, that oxalate of lime constitutes nearly one half of the weight 

 of a number of organized beings, performing an important part in 

 the economy of nature. It appears that by their means vegetation 

 has commenced on the surface of the earth, since they are found 



