216 



SCIENCE. 



[X. S. A'OL. II. No. 34. 



istics of living substances, whether in com- 

 plex or simple forms, to adapt themselves to 

 their environment. 



There is another fact in nature that the 

 microscope has revealed and that fills the 

 contemplative mind with wonder and an as- 

 piration to see a little farther into the liv- 

 ing substance, and so perchance discover 

 the hidden springs of action. This fact 

 maj' be called cellular altruism. In human 

 society the philanthropist and soldier are 

 ready at any time to sacrifice themselves 

 for the race or the nation. With the ani- 

 mals the guards of the flock or herd are 

 equally readj^ to die in its defense. 



So within each of the higher organisms 

 the microscope has shown a guarding host, 

 the leucocytes or white blood corpuscles. 

 The brilliant discoveries in the processes of 

 life with higher forms have shown that not 

 only is there a struggle for existence with 

 nature and against forms as large or larger 

 than themselves, but each organism is 

 liable to be undermined by forms, animal 

 and vegetable, infinitely smaller than them- 

 selves, insignificant and insiduous but 

 deadly. Now to guard the body against 

 these living particles and the particles of 

 dust that would tend to clog the system 

 there is a vast army of amoeba-like cells, 

 the leucocytes, that go wherever the body 

 is attacked and do battle. If the guards 

 succeed the organism lives and flourishes, 

 otherwise it dies or becomes weakened and 

 hampered. This much was common scien- 

 tific property three years ago, when one of 

 our members (Miss Edith J. Claypole) came 

 to my laboratory for advanced work. 1 dis- 

 cussed with her what has just been given, 

 and told her that there still remained to be 

 solved the problem what becomes of the 

 clogging or deleterious material which the 

 leucocyte take up? These bod}' guards 

 are after all a part of the organism, and for 

 tliem simply to engulf the material would 

 not rid the bodj' entirely of it, and finally 



an inevitable clogging of the system would 

 result. The problem is simple and definite: 

 What becomes of the deleterious substances, 

 bacteria and dust particles, that get into 

 the body and become engulfed by the leu- 

 cocj'tes? Fortunatelj', for the solution of 

 this problem, in our beautiful Cayuga Lake 

 there is an animal, the Necturus, with ex- 

 ternal gills through which the blood circu- 

 lates for its purification. So thin and trans- 

 parent is the covering tissiie in these gills 

 that one can see into the blood stream al- 

 most as easily as if it were uncovered. Every 

 solid constituent of the blood, whether red 

 corpuscle, white corpuscle, microbe or par- 

 ticle of dust, can be seen almost as clearly 

 as if mounted on a microscopic slide. 



Into the veins of this animal was injected 

 some lampblack mixed with water, a little 

 gum arable and ordinary salt, an entirely 

 non-poisonous mixture. Thousands of par- 

 ticles of carbon were thus introduced into 

 the blood and could be seen circulating 

 with it through the transparent gills. True 

 to their duty, the white corpuscles in a day 

 or two engulfed the carbon particles, but 

 for several days more the leucocytes could 

 be seen circulating with the blood stream 

 and carrying their load of coal with them. 

 Gradually the carbon laden corpuscles dis- 

 appeared and only the ordinarj' carbon-free 

 ones remained. Where had the carbon 

 been left? Had it been simply deposited 

 somewhere in the system ? The tissues 

 were fixed and serial sections made. The 

 natural pigment was bleached with hydro- 

 gen dioxid, so that if any carbon was pres- 

 ent it would show unmistakably. With the 

 exception of the spleen, no cai'bon appeared 

 in the tissues, but in many places the car- 

 bon-laden leucocytes were found. In 

 mucous cavities and on mucous surfaces 

 and on the surface of the skin were many 

 of them ; in the walls of organs were many 

 more apparently on their way to the sur- 

 face with the load, that is the carbon is 



