OF THE DIATOMACEiE. 
11 
CHAPTER II. 
OF THE DIATOMACEiE. 
These tjny members of the great vegetable kingdom are 
generally the first to engage the attention of the collector, 
for their distribution is almost boundless. I suppose there 
is scarcely a single piece of water anywhere which does 
not contain at least some individuals of the commoner 
species. They are to be found alike in the lake that 
crowns the mountain-top, and the swamps and peat-beds 
which fill the lowest valley ; in the water-course employed 
to irrigate the meadows ; in the broad ocean and the 
shallow puddle left by the overflowing of a ditch. The 
brackish water, where the tidal river meets the sea ; salt- 
works and salt-pits ; even inland lakes, which have a trace 
of salt in them— each affords a rich variety of characteristic 
Diatomaceas, varying according to the chemical quality of 
the water.* They are to be frequently found also on rocks 
and masses of stone, damp from overhanging trees, or from 
the constant trickling of water. There they nestle among 
the tufts of moss, or the layers, of Oscillatorige ; or, in 
company with other minute Alga?, form a slimy mass of a 
brown or olive green colour on the face of the bare rock. 
Never let the collector pass by a spot of this description 
without giving it a close examination. He will be often 
rewarded with some of the rarest and most lovely species. 
* It is quite astonishing what a slight infusion of salt suffices to 
fix the character of the Diatomacese. For example’s sake I may 
mention a lake in Hungary, and some pieces of water in Southern 
Moravia, which contain an inappreciable quantity of salt, neverthe- 
less the Diatomaceous forms answer exactly to those usually found 
in brackish water. — J. N. 
