154 THE AMERICAN MONTHLY [Jun 



use of a microscope the gathering will yield good result*. 

 Nitzschia frustulum, which Kutzing described, will be the 

 first gathering. Put it in paraiine paper — waxed paper 

 it is called — to keep it from drying up, and you may take 

 it along. 



Next notice the pools which have been left by the rain. 

 Here you will not get Bacillaria unless the pool has stood 

 a long time. But we dip a bottle full from the green or 

 yellowish green scum on the surface of the water, for it 

 may yield several forms or "species" of Navicula. You 

 may see on the rocks or mud just beneath the water's 

 edge, a dark-green mass of matter. Here you will most 

 certainly get Synedra, or Achanthidium, or even Melosira, 

 or other things. Get a dip there. On the stream that flows 

 from there you will get conferva, known by the brilliant 

 green color, covered with the same and perhaps Epithemia 

 and Cocconeis. On a larger pool, or a pond or lake, the 

 olive-green or yellowish-green scum is rich in Bacillaria 

 and you will get all that you can study. So fill your bot- 

 tles and spend many an hour over it when you get home 

 to your compound microscope. So much for recent fresh- 

 water Bacillaria. 



Now for marine forms. Along the shore, at going down 

 of the tide there are pools left which will yield Gramma- 

 tophora or Biddulphia or Melosira or Schizonema. Iu 

 the scum that collects on the sand you may get Epithe- 

 mia marina as it is called by A. S. Donkin. But marine 

 or fresh-water is the same and Epithema jurgensii, C. A. 

 A., must be the name. Alga although they are beautiful 

 and will yield hours of experience to those who study 

 them, we cannot get now for the alga? themselves but we 

 get them for the Bacillaria which cover them in countless 

 millions on every rock and pile where the sea goes. 



Fossil Bacillaria are more difficult to collect and study, 

 but if you have the opportunity you may collect any 

 light-colored and light-weight earth for them. Some 



