Maeoh 26, 1915] 



SCIENCE 



469 



surfaces within a few em. of the expanding 

 masses of cells, but local transpiration may- 

 have resulted in actual shrinkage. The opti- 

 mum temperature for this plant is also a fea- 

 ture not yet determined. 



The growth of the opuntias therefore takes 

 place during a period of decreasing' acidity re- 

 sulting from the disintegrating action of light 

 and rising temperatures. This statement ap- 

 plies not only to the diurnal behavior of the 

 plants during the growing season, but to the 

 growing season as a whole, which as Dr. H. M. 

 Eichards has pointed out in a paper now in 

 press is one of diminishing acidity. The acidi- 

 ties of the cacti are calculated for the sap of 

 the plants. The acidities of N/lOO to N/3,000 

 found by Borowikow to be favorable for hydra- 

 tation and growth were of the culture solution ; 

 that of the sap of the seedling used was prob- 

 ably still much lower. 



Light and temperature in lesser degree are 

 seen to exercise a totalized releasing effect on 

 growth coincident with reduced acidity and 

 increased hydratation, to a certain limit. 

 Beyond this grovrth rate is checked. Further 

 analytical tests will be necessary to determine 

 the limiting factors. 



D. T. MacDougal 



Deseet Botanical Laboeatoet 



PBOCEEDINGS OF TBE ANNUAL MEETING 

 OF THE AMERICAN SOCIETY OF 

 ZOOLOGISTS HELD IN PHILA- 

 DELPHIA, mU. II 

 Multiple Human Births: G. H. Paekee. 



Multiple births are well knowa among human, 

 beings and the proportions of twins, triplets, and 

 quadruplets to single births have often been re- 

 corded. Instances of five and six children at a 

 birth are very rare but apparently well authenti- 

 cated. All eases above sis are very doubtful. In 

 the Boston Medical and Surgical Journal, Volume 

 10, page 224, 1872, is recorded from Trumbull 

 County, Ohio, a case of eight children at a birth. 

 This very circumstantial account, which has been 

 quoted in numerous books and journals, proves on 

 investigation by the county clerk of Trumbull 

 County to be entirely fictitious. 



Comparative and General Physiology 



Effect of Electrolytes Upon the Sate of Nerve 



Conduction in Cassiopea: Alfeed Gt. Maybe. 



Further Studies on the Behavior of Amceba: Asa 



A. SCHAEFFEE. 



The Significance of Certain Internal Conditions of 

 the Organism in Organic Evolution : F. H. Pike 

 AND E. B. Scott. 



Zoologists, while studying the phenomena of 

 form regulation in animals, have given compara- 

 tively little thought to the regulation of internal 

 conditions — the changes in matter and energy in 

 the organisms which underly the changes of form. 

 The data accumulated in the physiological lab- 

 oratories show that in the higher animals there is 

 a regulation, varying within relatively narrow lim- 

 its, of body temperature, the blood pressure, the 

 tension of carbon dioxide and oxygen, of the con- 

 centration of hydrogen and hydroxyl ions, of the 

 osmotic pressure, and of the general composition, 

 quantitative as well as qualitative, of the fluids of 

 the body, brought about by a number of systems 

 and organs of the body. 



From the point of view of the physical chemist, 

 the general constancy of internal conditions of 

 the higher organism may be interpreted in terms 

 of chemical equilibrium. If the reactions within 

 the body are of the nature of the "slow" reactions 

 of the chemical laboratory, the constant tempera- 

 ture and the constant physico-chemical concentra- 

 tion of the body fluids would be attended by a 

 speed of reaction within the body which would be, 

 in a considerable degree, independent of the con- 

 ditions in the environment. The internal mechan- 

 isms of the organisms lie at the base of the dimin- 

 ishing effect of the environment, or the greater 

 degree of independence of the animal from the 

 conditions of the environment as the organisms 

 occupy successively higher positions in the evolu- 

 tionary scale. 



Experiments on X-Eadiation as the Cause of Per- 

 meability Changes: A. Eichakds. 

 Some Factors Concerned in the Death of Para- 

 mcecium at High Temperatures: M. H. Jacobs. 

 The Effect of Color in the Environment on the 

 Color Changes of AnoUs Carolinensis : Manton 



COPELAND. 



It is well known that the so-called Florida 

 chameleon, Anolis carolinensis Cuv., becomes green 

 in the dark and almost invariably turns brown in 

 daylight. To test the effect of color in the en- 

 vironment on the color changes in the skin of the 

 lizard, the animals were placed in boxes lined in 

 part with colored paper and exposed to daylight. 

 It was found that the green color was often as- 

 sumed under such conditions. A yellow environ- 

 ment always induced a change from brown to 



