676 



AN EFFLORESCENCE ON SOME NEW ZEALAND 



KELPS. 



By a. H. S. Lucas, M.A., B.Sc. 



In December, 1910, I received a parcel of Algse from Welling- 

 ton, N.Z. After washing with fresh water and drying in the 

 open air, I deposited specimens of some of the larger kelps, 

 Lessonia vrwiegata J. Ag., Marginai-ia Boryana (Rich.) Mont., 

 and M. Urvilleana Rich , in a large cardboard box, and thus pre- 

 served them in a dry room. On looking over these specimens in 

 June, 1915, I found them covered with a beautiful efflorescence 

 of delicate needle-shaped cr3'stals, some of them nearly a centi- 

 metre in length. They were singly colourless and flexible. The 

 crystals had formed in such quantities that, by sliaking the alg?e, 

 I was able to collect several grams of them. They were entirely 

 soluble in water. 



I made a large number of preliminary tests with them in the 

 laboratory of the Sydney Grammar School. The flame was as pure 

 a potassium flame as I could obtain from crystals of potassium 

 chloride taken from the laboratory stock. I could not obtain 

 any evidence of the presence of any other metal. The abundant 

 precipitate with silver nitrate indicated that the potassium was 

 mainly present as chloride. I could find no trace of sulphates 

 or any other inorganic salts. There were no signs at all of 

 iodine or bromine. That organic substances were present was 

 soon discovered; and, notably, the reduction of copper sulphate 

 in the presence of sugars showed the presence of OH radicals. 

 The solution behaved just as would a solution of a tartrate or a 

 citrate, while Fehling's solution gave no evidence of sugars. I 

 could not obtain, however, independent evidence of the presence 

 of tartrates or citrates. 



