1894.] MICROSCOPICAL JOURNAL. 229 



As all the results noted by myself, therein, were secured 

 without the use of staining agents, or pigmentary colors, 

 I conducted the new series of researches with the aid of 

 water color pigments. I selected for the first trial, 

 Prussian blue, in place of indigo. With a camel's hair 

 brush, I transferred a small dab of color from the moist 

 cake of blue, to the centre of a glass slip, and then with 

 a rubber bulb tube, I deposited thereon a dip from a 

 concentration of freshly gathered living diatoms. Plac- 

 ing the slide upon the stage, and adjusting a half inch 

 lens to the tube, so as to secure a large field, I explored 

 for specimens of active Navicula major, and having 

 brought one to the center of the field, the half inch lens 

 was changed for a sixth inch (Zeiss D) lens. 



The N. major selected for study, offered its sutural 

 face to the view. On confining my attention closely to 

 its peripheral portions, I very promptly observed the 

 characteristic molecular activity at the nodular cavities, 

 and while reviewing these points, I witnessed in this 

 single initial specimen (and so was enabled to corroborate 

 and verify), all that had been previously described and 

 figured by Prof. H. L. Smith in his paper. Finding that 

 it was relatively easy to watch continuously all the phases 

 of epidermal activity associated with the diatom, I set 

 myself to master the character and causes of these varied 

 living activities. And now after more than thirty days 

 from the inception of the study with pigments and after 

 devoting several hours each night of that period to obser- 

 vation of the living diatoms, I feel confident that the 

 diatom will not offer further mystery as to its vital 

 potentialities, except as to two absorbing metaphysical 

 questions. These are : as to how its life may have ori- 

 ginated and continues to manifest itself in the ordinarily 

 hyaline protoplasmic matter characteristic of the initial 

 beginnings of all life of which man has any cognizance ; 

 and second, the nature of the diatom's inherent chemico- 



