'^'■^2 The Microscope. 



upon a description of my methods, feeling the utmost confidence in 

 the reliability of the results obtained. Having, likewise, given the 

 study of the diatomacese preference over all others requiring the appli- 

 cation of the microscope, w^hether for purposes of pleasure or of profit; 

 it is, therefore, in this branch that I am most interested, and from 

 the very inception of my studies, I have had in view the accomplish- 

 ment of a definite end, namely, to elaborate from all possible and 

 available sources as complete a table or synopsis as is possible, of the 

 various genera and species of the Diatomaceoe occurring wittiiu a 

 radius of at least fifty miles of the city of Mobile. And as, during 

 the past ten years, I have availed myself of such opportunities as were 

 presented to collect or secure material yielding diatoms, I will enu- 

 merate some of the sources drawn upon. 



The chiefest among these are the marine muds of Mobile Bay 

 and the Gulf of Mexico; the marine muds also presenting the great- 

 est difficulties to be overcome in their preparation as a source of 

 diatoms for study or for exchange. Also, the sedimentary muds, 

 and water plants of every accessible local river, creek, bayou, lake, 

 swamp, marsh, pond or spi'ing, and even ditches; each contributing 

 its quota of species, in various combinations or associations. Among 

 the more novel sources may be mentioned the "guano" of the liv- 

 ing sea gull and the gizzards (so called) of the mullet fish, both afford- 

 ing diatoms in great profusion, and, not to overlook the latest found 

 soiirce in my experience, the ancient marsh mud, on which rests the 

 alluvium, upon which the city of Mobile is built. This stratum was 

 met with at a depth of five feet below the level of the sti'eets border- 

 ing on the river. I think I can safely say that through my exertions 

 in prosecuting this " labor of love" I have been able to demonstrate 

 the occurrence of at least three hundred distinct species of diatoms 

 closely tributary to this centre, and of which I have preserved 

 mounted slides for future reference or use, in concluding my primary 

 object. The first requisite in the preparation of marine diatoms is 

 to secure a quantity of mud, and the subsequent treatment as pur- 

 sued by the writer is as follows: Take at least half a pound of hard 

 or soft mud to begin on, and soften it into a uniform liquid paste, 

 and, to hasten and assist its liquidity, add about a teaspoonful of 

 aqua ammonia, which liquid will be useful under all circumstances 

 in the initial steps of cleaning, as it cuts and dissolves slimes and 

 gelatinous impurities, and cleans the sand grains, and enables the 

 l)ulk of the material to be cleaned to settle (juickly and compactly, as 

 well as having distinct lubricating properties. Next, transfer the 



