1894 THE MICROSCOPE. 187 



situation possible. In conclusion, I would invite all interested 

 in the Diatoms, to make the trials, tests and verifications for 

 themselves, before condemning or criticising too harshly the 

 methods which in a moment of unsophisticated thought I 

 deemed worthy of publication. 



For sixteen years I have been a reader of one or both of our 

 Journals devoted to Microscopic Science, and of The Microscope 

 during Dr. Alfred C. Stokes' editorial management of it. I had 

 learned to appreciate the brilliant, but somewhat impetuous 

 style of his editorials, and later of his Biological contributions. 

 I envied the facileness of his pen. Bat when struggling genius 

 spreading its pinions for a trial flight, is rudely struck at, it does 

 not expect to see a friend in exultation. — K. M. Cunningham. 



On the Animality of the Daitom.— Mr. Cunningham sends 

 us the following which he has rceived relative to his late paper: 



I take the Amer. Mo. Micr. Jour, and had therefore seen your 

 second article which contains much that is of interest to me, 

 although I have not had any reason so far to differ from the 

 views of the Rev. W. Smith and the numerous other diatomists 

 who have followed him in regard to the plant nature of the 

 Diatom. I think it foolish of anyone to be dogmatic on the 

 subject and to refuse to allow those who follow Ehrenberg in 

 considering the possibility of it turning out to belong to the 

 Protozoans to show^ cause why the question should be re-dis- 

 cussed. I can entirely and positively confirm your observation 

 of the power of the Diatom to move rapidly objects of various 

 size along its surface. Three weeke ago I had the pleasure of ob- 

 serving with a Nachet's }, the comparatively small Navicula 

 radiosa rapidly move a mass of mucous matter of at least a 

 fourth of its own size in which a number of minute grains of 

 sand were embedded, backwards and forwards from extreme 

 end to extreme end of the surface of the frustule (valvular or 

 side view). I counted thirty return journeys of the load during 

 which time the diatom itself was moving about in a verv active 

 manner, and the journeys which never ceased for a second while 

 the diatom was in sight would have apparently been continued 

 had not the load been got rid of by the diatom entering a thicket 

 which caught the traveller and reheved the diatom of its bur- 

 den. Although simple and plausible, I do notbelieve in the en- 



