Journal 



OF THE 



NEW-YORK MICROSCOPICAL SOCIETY 



Vol. IX. OCTOBER, 1893. No. 4. 



NOTES ON SOME RESEARCHES AMONG THE 

 DIATOMACE^. 



BY K. M. CUNNINGHAM. 

 (^Read November i-jth^ 1893.) 



By a peculiar trend of events my attention had recently been 

 called to the question of the plant or animal nature of the dia- 

 toms. This question had hitherto been of little interest to me, 

 very nearly all of my interest having been directed merely to an 

 accumulation of specimens of fossil or recent deposits and the 

 study of their distribution. But certain favorable opportunities 

 have enabled me recsntly to devote some attention to the study 

 of living diatoms. With this object in view I have prepared, and, 

 after due study of the same, I send herewith the series of slides 

 illustrating this paper as a donation to the Society. 



It may be of historic interest to recall the fact that in the 

 " Smithsonian Contributions to Knowledge " there is a publica- 

 tion, bearing the date of 1850, and entitled " Microscopical Obser- 

 vations made by J. W. Bailey, of West Point, N. Y., during a 

 tour through the States of South Carolina, Georgia, and Florida," 

 in which work were listed and tabulated all infusorial and other 

 microscopic forms of life encountered in his travels through the 

 said territory, including the diatoms and the desmids, with fig- 

 ures of the new species found by himself. Since the year 1878, 



