222 The Monad's Place in Nature. 



A similar examination of Oscillatoria with Lyngbya reveals the 

 same transition. Were it not that the forms are too common for 

 a diagram, I have abundant evidence in my notes in proof of my 

 opinion. The point, however, is one capable of investigation by 

 comparatively low powers of the microscope, and may form a very 

 interesting point for young observers to commence a systematic use 

 of microscopical investigation by means of notes and careful drawing. 

 And here I would trespass upon the pages of ' M. M. J.' by offering 

 this suggestion, that young microscopists, instead of using their 

 instrument as a mere toy to look at strange and beautiful objects 

 without system, might confer great benefit upon the cause of science 

 by taking up this subject and carefully working it out. It is a 

 mistake into which many men fall when they suppose that they are 

 unable to help the cause of science by microscopic research. I am 

 convinced that honest and careful tabulated experience is always 

 valuable, and the more so as it is multiplied by many experimenters. 

 If we look upon the broad face of any landscape we are at once 

 struck with the growth of green verdure upon all surfaces wliich 

 are rough enough to receive the air-borne seed of plants, and have 

 remained long enough undisturbed to allow of the development of 

 this verdure. 



An observation of it under various conditions shows various 

 forms of development, and as it is in most cases evident to the 

 simplest consideration that the product is air sown, so it also 

 becomes evident from the facts before us that the source of it is 

 some matter of constant existence in the air. Now, an examination 

 of the air shows us occasional green Gonidia which manifestly have 

 sprung from lichens or mosses, from the elastic membrane concerned 

 in the bursting of apothecia of lichens on the one hand, and the 

 bursting of tubules of mosses as shown by Dr. Hicks on the other; 

 and the facts adduced in this paper relative to the bursting of 

 vacuoles of Vaucheria, Pseudo-gonidia, and of the tubules of Con- 

 ferva rivularis, give us evidence of a source whence the seeds of 

 these plants may be ejected into the air. This being the case, it 

 becomes necessary to observe the results of this sowing of seed 

 under proper means of observation. I have in my study at the 

 present time a large quantity of green Lyngbya, which owes its 

 existence to a small number of cellules of Chlorococcus, which was 

 sown by the air upon a lint siphon which I used for the purpose 

 of collecting air-borne seeds about two years ago. 



In a previous number of ' M, M. J.' I showed how four distinct 

 species of moss gave off similar Gonidia, which produced Chloro- 

 coccus and Lyngbya, and every day's experience confirms these 

 observations. 



But the experiment upon the fluff and dust as detailed in this 

 paper points more distinctly to the pin-point Monad as the source 



