1900] MICROSCOPICAL JOURNAL. 153 



certain minute and numerous dots or cells. They are of 

 a different refractive index from the surrounding proto- 

 plasm and of oily consistence. They are in trembling 

 motion and seem to he anthozoa or male organs. After a 

 time they come to a rest or to disappear or they appear 

 quiescent. Before they do so there appear certain larger 

 bodies which instead of being called dots are known as 

 oil globules. They are much larger than the anthozoa and 

 seem to be made up of a dense' oily substance, but like 

 the anthozoa have no limiting membrane. They occur 

 mostly only as two, one in each half of the Bacillariau. 

 They are also at rest. They seem to be ova or female or- 

 gans. This is the composition of a full individual of a 

 Bacillariau and is all that we know positively concern- 

 ing them. 



Let us now go after the Bacillaria or Diatom-hunting 

 as it is called. We provide ourselves with some two-ounce 

 corked bottles with large'open mouths. We can take one 

 or more Tfith us, but an enthusiast will have several, one 

 or more in each pocket. We will take a lunch, for we are 

 going a long distance and will be away a long time, all 

 day perhaps. We can take a pocket microscope with us. 

 I mean a compound microscope magnifying about fifty or 

 ahundred diameters, such as can be bought for a couple of 

 dollars. Of course the pocket lens will always be present, 

 for everybody should have a pocket lens always with his 

 knife and purse. I sjiould not feel I was dressed without 

 my pocket lens. 



Being equipped with stout old shoes, we travel along 

 a road but soon we see a mass of water that looks prom- 

 ising. We get over the farmer's fence into his grounds 

 and go for it. If weather has been dry, we see green scum 

 on the earth. This may consist of Protococcus and dia- 

 toms or it may contain Protococcus alone. At all events 

 the forms of Bacillaria are smallest of the small and can- 

 not be studied by the tyro. But to one advanced in the 



