DIATOMS 45 
century, though for part of the time the water was frozen, 
and for a considerable time they were kept in the dark. 
Diatoms are found throughout the world. Several 
species are common from the polar regions to the equator. 
They are found on mountain tops, in caverns, in water 
direct from glaciers, and in springs having a temperature 
of 164° Fahrenheit. Sixty years ago Hooker found deposits 
extending hundreds of miles in the Antaretic Ocean; and in 
1856 the Grinnell expedition in search of Franklin reported 
that the northern polar seas ‘‘ are filled with slimy diatom- 
aceous life ;’’ and Carpenter, at a later date, found the bot- 
tom of the sea nearer the equator ‘‘covered with diatom- 
ooze.’’ Diatoms played a part in the inception of Nanson’s” 
polar voyage. A dozen species of Diatoms peculiar to 
Northern Asia had been found on ice-floes at Bering Strait, 
the opposite side of the world, and Nanson, convinced that 
that they had drifted there over the Polar Sea, concluded 
‘that with this same drift-ice and by the same route’’ he 
could drift on the ‘‘ Fram.”’ . 
Fossil Diatoms are also found throughout the world. 
Of them time permits me only to say, that as at Richmond, 
Va., and on the banks of the Colorado River, their flinty 
skeletons rest, as they have rested for ages in deposits 
many feet in thickness and many milesinlength. The com- 
plete history of fossil Diatoms is a chapter of the great stone 
book awaiting a transcriber ; and the monographs, written 
here and there, warrant belief that such a record would be 
an interesting addition to palzography. 
This district with its lake, bay, streams and springs 
offers special opportunity for study of the Diatomacee. 
Many freshwater species are readily found, and it is pleas- 
ing to know that our Association has not been altogether 
unmindful of these advantages. Occasionally a collector of 
Diatoms is flouted as a ‘‘diatomaniac.’’ But wisdom is 
justified of her children. It is no idle pastime to make a 
study of organisms which, if minute, exist in myriads upon 
