THE VICTORIAN NATURALIST. 



Epithemia zebra, Ehr., Eunotia, sp., Synedra, sp. (fragments), 

 Feronia, sp., Diatoma, sp. (some examples still sliowing the 

 gelatinous envelope), Hanlzschia amphioxus, Grunow, Hantzschia, 

 sp., JVitzschia, sp. (several), Melosira, sp. (several). 



The question of the derivation, as also the destination, of so 

 many species of diatoms, and other organisms much more potent 

 in their consequential effects, and such as it appears must he 

 regularly carried by these periodic cyclonic storms, is one of 

 great interest. This is so, not merely because of its bearing upon 

 the distribution of one particular group of microscopical plants 

 through a given area, but rather because of its relation to 

 questions affecting the welfare of communities separated by 

 hundreds of miles of land and sea For it must be perfectly 

 clear that if individual organisms so large as the frustules of the 

 diatoms we have enumerated can be carried from the northern 

 areas of Victoria to New Zealand, of which more anon, it is 

 equally clear that the organisms in their embryonic state, 

 infinately smaller, but more potent in their effects upon other 

 organisms — to wit, ourselves — may be, and indeed are, carried in 

 the careering dust storms with which the Melbournians are, alas ! 

 only too familiar. 



In order, if possible, to derive definite information upon this 

 point, we submitted samples of the material obtained to Dr. 

 Bull, Lecturer on Bacteriology at the University, who generously 

 undertook to prepare cultures from the several tubes of sediment. 

 Unfortunately these could not be immediately dealt with ; so 

 that, according to Dr. Bull's appended report, only the more 

 resistant organisms were capable of development. In addition 

 to the saprophytic and allied organisms alluded to by Dr. Bull, 

 numerous protozoan forms of life, chiefly of the flagellate type, 

 quickly developed out in a tube of material left for a few days 

 exposed to the light. Of course the usual precautionary measures 

 to ensure isolation and freedom from contamination other than 

 such as was unavoidable at the time of collection had been 

 taken. 



Report on the Bacteriological Examination of Two 

 Specimens of "Red-Rain" Water. By Dr. R. J. Bull. 

 The samples were labelled as under : — 



1. " Red rain," collected St. Kilda, 14/2/03. 



2. "Red rain" ,, „ 2S/3/03. 



Mode of Examination. — Small measured quantities of the 

 turbid water (from -\j to ^V cubic centimetre) were inoculated 

 into plates of sterile gelatine and tubes of nutrient agar, and 

 the colonies of bacteria present were studied as they developed. 



liesults. — No. I, although containing more than twice as much 

 sediment as No. 2, contained considerably fewer micro-organisms. 



