192 PEOGRESS OF MICROSCOPICAL SCIENCE. 



bottles cryptogams taken from water that had been kept in iron 

 vessels. The following are the results at which he arrived^ from 

 examination made after many months, the bottles having been in the 

 meantime well closed. 1. Some cryptogamic plants are capable of 

 taking up metallic oxides (lead, iron, &c,), and forming organic com- 

 binations. 2. For the formation of the organic structures, water is 

 not sufificient; the presence of carbon, &c., appears to be necessary. 

 While vegetations were developed in great numbers in the bottle in 

 which acetate of lead had been placed, very few were formed in that 

 containing minium. 3. For the testing of drinking water for lead, 

 the ordinary reactions of sulphydric acid or sulphide of ammonium 

 is insufficient. A large quantity of the water must be allowed to 

 stand ; after the upper part has been decanted off, the lower portion 

 must be boiled down to a minimum and treated with strong hydro- 

 chloric acid. 4. The result of experiments made by treating the 

 plants containing lead with a mixture of glycerine and pepsine 

 renders it very probable that, when cryptogamic vegetations containing 

 the metal are taken into the stomach, lead is separated from them by 

 the gastric juice. The use of load in water pipes is to be avoided ; 

 and if it be necessary to use water in which cryptogams containing 

 lead are present, it should be allowed to stand, the lower portion 

 should be rejected, and the water filtered before being used. 



Herr Huizinga on Ahiogenesis. — In the ' Centralblatt ' (xv. 1873) 

 Herr 0. Huizinga suggests a mode of dealing with the ahiogenesis 

 question. He refers * to and repeats Bastian's and Sanderson's experi- 

 ments on the development of low organisms in turnij) infusions con- 

 taining various salts, and finds that no bacteria are developed if the 

 contents of the vessel be boiled, and whilst boiling the vessel be 

 closed with a cap of filter paper. He remarks, however, that the 

 paper might easily be the means of the introduction of germs, and that 

 the only certain protection against such introduction is afforded 

 by some material that can be strongly heated. He accordingly re- 

 commends certain plates named in Germany " Estricken," and which 

 appear to be equivalent to our porous earthenware. Of these he makes 

 stoppers that are luted into tlie mouths of the flasks, when their con- 

 tents are boiling, with asphalte. Such stoi)pers permit the passage 

 of air, but perfectly occlude the passage of germs. To in-ove this, lie 

 took two flasks containing solution of salt and ammonium tartrate. 

 Into one he inserted a small quantity of dust collected in a room con- 

 taining decomposing substances, as urine, whilst the other was closed 

 when boiling and some of the dust distributed on the surface of the 

 stopper. In twenty-four hours the first solution was already troubled, 

 and soon after abundant bacteria appeared, whilst the other remained 

 clear for more than a week, but was not further examined. 



Wltat is and lohat sliould he the Work of Local Natural History and 

 Microscopical Societies. — Professor Gulliver gives his views on this 

 matter in a contemporary, and as they arc, in our opinion, of consider- 

 able importance, we quote them for our readers.f Talking of the 



* ' Lancet,' July 12th. t See ' Nature,' May 22. 



