which have broug 

 thrix in the Emm 

 lit.' soil was prepared by industrial dejections, especially those 

 (• mi distilleries, which discharge nitrates in abundance into the 

 water-bearing stratum, at certain places very near the surface. 

 ' i the vicinity of swamps and ponds, 

 , irons of Berlin. 



relatively dry, the water-level was 

 le rains of the spring and the begin- 

 ning of the summer suddenly raised it, and carried with them the 

 vegetable productions or the animals which had been developed 

 in the humid earth. 



While at Lille the Crenothrix was thus brought in abundance 

 into the Emmerin reservoirs and the water-pipes, several wells 

 at Tourcoing furnished balls of a fine Oligochsete worm (Phreoryctes 

 Menkeanus), till then unknown in France. 



Lastly,a portion of the aqueduct is dug in the aquiferous chalk; 

 and it was thought needless to arch over that part; moreover, 

 inlets have been pierced in order to increase by drainage-water 

 the supply furnished hv the springs. Kvery time that the flow of 

 the water' is made more rapid, in that part <>f the aquiferous layer 

 :i veritable aspiration is produced, which carries into the aqueduct 

 the spores and filaments of the Crenothrix, which a slower and 

 "i"i" complete filtration woidd have retained in the soil. 

 medy this scourge, 



Berlin by Zopf and Brefeld. 



Towns establishing new systems id' canals of potable water will 

 do well, in order to avoid the (frrnnt ///•/>, to take the sources in 

 the deep strata, to avoid waters containing sabs of protoxide of 

 iron (necessary to the vegetation of this Schizomycete), and to 

 prefer to subterranean waters the more aerated waters of lakes 

 remote from all industrial establishments.— Comptes Pendvs, July 

 31, 1882, xcv, 247-249. Ann. Ma,/. Xat. ///V., Sept. 1882. 



■">. Transactions af the Anohun/' 'of Sciences of St. Louis, Vol. 

 iv, No. 2. St. Louis, Missouri, 1882.— This number contains 

 among its scientific papers memoirs by C. V. Rilky on N. A. Mi- 

 crogasters with descriptions of new species, and on new Tort n- 

 (,1 'h>'; by V. K. Nii-iiki:, on problems in refraction, and magnetic 

 determinations in Missouri in IS80; by C. A. Toon, on reversion 

 of type in the digastric muscle of man ; IT. S. Pritchktt, an 

 "I'li'in.ris ,,f Mars for tie- opposition of |ss] ; (i. Esuki.maxs, on 

 the genus Isoetes in North America; E. A. Engler, on auroral 

 phenomena of Sept, 12, 1881. 



6. Journal and Proceedings of the Royal Society of New 

 s "" f i> Wales. 1881. Vol. xv. Edited by A. Liversidoe, Prof. 



