l886.] NEW-YORK MICROSCOPICAL SOCIETY. 156 



while since I've given him anything.' So it was agreed to send 

 it at first chance. Though when it come to the point, I did kind 

 o' hate to take it down from granny's photo' which it had dressed 

 up for a round year." This was indeed a damper, but happily 

 not an extinguisher. It was now evident that the Sertularia had 

 nothing to do with my crop of diatoms. Resolved, to get at the 

 bottom of the mystery, if possible, I began a series of experi- 

 ments, and designated this initial experience " Experiment No. 

 I." To the jar used I attached a label bearing the letter A. 

 As the jar was really an aquarium, it had not been covered, but 

 I now put on the top a piece of glass. 



Again was the demijohn brought from the cellar, and a pint 

 jar was nearly filled with the water a little roiled. This was 

 labelled B and, covered with glass, was placed in the window 

 beside A. This experiment No. 2 was started early in January, 

 1883. In about four weeks I detected a trace of sediment in 

 the jar. A fertile drop of this was placed under the microscope, 

 and lo ! there they were, diatoms again. But this was only the 

 beginning of experiment No. 2. In a few weeks the sediment 

 at the bottom of the jar had thickened, as also had the film on 

 the sides. In a word, this second crop of diatoms had become 

 very abundant, and promised soon to quite equal in numbers 

 the first one. 



I was now firm in my belief that I was raising diatoms from 

 the spores, although I could not yet say that this was proven. 

 I next began a careful examination of the sediment in the demi- 

 john, supposing that if there were any diatoms in the mud 

 which caused the discoloration of the water when it was obtained 

 from the Bay, be they now dead or alive, something should be 

 learned from them. I found a number of forms, all, however, 

 quite large in comparison with those bred in the jars. There 

 were Pleurosigma, Surirella, a large Navicula, an Achnanthes, a 

 Coscinodiscus, and several discoidal and other forms. They were, 

 however, all dead, and, of them all, only one genus, and but 

 one species, was represented among the diatoms in the breeding 

 jars. True, in the sediment of the jars would be found, but 

 very rarely, one of these dead forms which had been carried 

 there in the agitated sediment from the demijohn. 



This examination and comparison was entered as experiment 

 No. 3. It seemed to furnish reasonable ground for the 



