Mat 19, 1916] 



SCIENCE 



725 



velopment constitute a period of rejuvenescence. 

 Many other periodicities in organisms are of the 

 same general nature as the age cycle. Fatigue, re- 

 covery, the loading and discharge of gland cells, va- 

 rious seasonal periodicities, alternating active and 

 quiescent periods, etc., depend to a greater or less 

 degree on modifications of the protoplasm by meta- 

 bolism and the following removal of such modifi- 

 cations under altered metabolic conditions. 



Cooperation as a Factor in Evolution: William 

 Patten. (Introduced by Professor H. H. Don- 

 aldson.) 



The purpose of this discussion is to show that 

 cooperation, or the summation of power, is the 

 creative and preservative agent in evolution, and 

 that the summation of power depends on coopera- 

 tion in the conveyance of power. The vis a tergo 

 in life is the product of internal cooperative ex- 

 change (metabolism). Growth is profitable ex- 

 change, or the increase of the power of exchange 

 due to the local accumulation of those agents whose 

 demands are the impetus to exchange. The rate 

 at which growth proceeds depends on the capacity 

 of its conveyers, that is on their capacity to con- 

 vey things to and from the growing points, or the 

 growing points to the sources of supplies. Growth 

 creates a power which is used as a means to satisfy 

 its own demands, and a surplus power for "free- 

 dom" of action, which is used to experiment and 

 explore, or to find better ways and means of satis- 

 fying its demands. Growth, therefore, follows the 

 easiest, most accessible, and most profitable lines 

 of conveyance, and its products accumulate along 

 the lines of least resistance. Growth inevitably 

 creates diversified conditions which tend to check 

 its own progress till relieved by better coopera- 

 tion. For growth reduces the immediately avail- 

 able supplies, thereby requiring greater expendi- 

 tures to procure them; and the new internal condi- 

 tions created by growth create new products, with 

 new demands, faster than the right ways of minis- 

 tering to them can be found. The larger de- 

 mands, under reduced resources, can only be sup- 

 plied by better cooperation in the common serv- 

 ice of conveyance; but as fast as these demands 

 are satisfied, producing new growths, further de- 

 mands are created, to satisfy which requires still 

 better methods of cooperation. The same laws 

 which prevail in the inner and outer life of ani- 

 mals and plants prevail in the social life of man. 

 Man's social progress is measured by the degree 

 to which he has extended the mutually profitable 

 give and take of cooperative action beyond him- 



self, to the family, tribe, state and into the world 

 of life at large. The chief agents of civilization, 

 language, commerce, science, literature, art and 

 religion are the larger and more enduring instru- 

 ments of conveyance, which better enable the part 

 and the whole to avoid that which is 'evil" and 

 to find that which is "good," and which yields a 

 larger surplus for "freedom." 

 On the Effects of Continued Administration of 

 Certain Poisons to the Domestic Fowl, with Spe- 

 cial Reference to the Progeny: Raymond Pearl. 

 Types of Neuromuscular Mechanism in Sea- Ane- 

 mones: George H. Parker. 

 In the origin of nerve and muscle the sea-anemone 

 has been supposed to represent a step in which a 

 nervous set of very primitive structure could throw 

 into prolonged contraction the general musculature 

 of the animal's body. An examination of the body 

 of the sea-anemone shows that its muscular activ- 

 ities are of a much more diverse kind. They in- 

 clude, first, muscles that act under direct stimula- 

 tion and without the intervention of nerves; sec- 

 ondly, muscles that are stimulated directly as well 

 as by nerves; thirdly, muscles that are stimulated 

 only by nerves and exhibit under these circum- 

 stances profound tonic contractions; and, finally, 

 muscles that react in the same reflex way that 

 those in the higher animals do. This diversity of 

 muscular response has not been fully appreciated 

 by previous workers. 



Determination of Stellar Magnitudes iy Plwtog- 

 raphy: Edward C. Pickering. 

 An immense amount of work is being carried on 

 by observatories all over the world, in determining 

 the photographic magnitudes of the stars. It is 

 of the utmost importance that all of these magni- 

 tudes should be reduced to the same scale. Ac- 

 cordingly, in April, 1909, an International Com- 

 mittee was appointed with members from Eng- 

 land, France, Germany, Holland, Russia and the 

 United States. This committee met in 1910 and 

 1913, and, after a most amicable discussion, agreed 

 on a system, in which all stars were to be referred 

 to a Standard Sequence of stars near the North 

 Pole. The magnitudes of the latter were deter- 

 mined at Harvard by Miss H. S. Leavitt, by six 

 different methods, using eleven different telescopes, 

 having apertures from one half to sixty inches. 

 All gave accordant results, and were adopted by 

 the committee. A simple method was found for 

 transferring these magnitudes to stars in other 

 parts of the sky, but here extraordinary sources of 

 systematic errors presented themselves. For in- 



