1899] MICROSCOPICAL JOURNAL. 87 



former made at least one grating on an alloy of platinum 

 and gold, which, when placed in the sunlight is one of the 

 most gorgeously beautiful objects the human eye ever 

 rested upon. All the colors of the prismatic spectrum are 

 reflected from the lenticular surface, and the phenomena 

 of interference cause the little button to glow like a liv- 

 ing coal, sending forth light rays of a myriad hues, yet 

 so soft, withal, that the eye can rest upon it without fa- 

 tigue for several minutes. — Nat. Drug. 



Experiments in the Artificial Culture of Diatoms. 



William A. Terry. 



In the summer of 1895, I spent some time in exploring 

 the marshes, ditches, and pond holes of the valley of the 

 West River, between New Haven and West Haven, to in- 

 vestigate the diatoms of that locality, some account of 

 which has been previously published in this journal. The 

 N. Y. & N. H. railroad at that time crossed this marsh on 

 a long trestle-work which was provided with a series of 

 water tanks for use in case of fire. I made inquiries of 

 the official in charge of this bridge as to the possibility 

 of crossing the marsh in various directions. When he 

 understood I was in search of microscopical material he 

 called my attention to these tanks. The water they con- 

 tained was saturated with salt to prevent freezing, and 

 he said the professors of Yale College claimed they held 

 an organism that could not be found elsewhere this side 

 of Salt Lake, Utah. On examining these tanks, I found 

 the one directly over West River to be swarming with 

 Artemia gracilis, the so-called "brine shrimp." They 

 were quite large, mature, and loaded with eggs, which 

 looked under the microscope like bunches of grapes. The 

 ditches on both sides of Washington street where it 

 crosses the marsh, connect with a small brook flowing 

 from West Haven. At low tide the mud laid bare in 



