744 



SCIENCE. 



[N. S. Vol. XVI. No. 410. 



females of wliich were found crowded with 

 young' shells in a marsupium similar to that 

 of Sphwrium, not resembling that of Thecalia, 

 and other Carditid83 in the ventral portion of 

 the mantle, but in the dorsal region of the 

 body. Specimens from the Aleutian Islands 

 were in this condition about June 1, while in 

 the Polar Sea, near Point Barrow, it occurs in 

 August. 



Dr. R. E. B. McKenney spoke on ' Luminous 

 Bacteria.' He briefly reviewed the work done 

 on the luminous bacteria during the past quar- 

 ter of a century and recorded some of his own 

 observations. In all cases the temperature 

 limits for light production are within those 

 for growth. As soon as the temperature passes 

 beyond limits for normal light production, 

 light instantly disappears. Bacillus phos- 

 phorescens, Fischer, when grown for a number 

 of generations at 35° C, which is 5° above 

 the maximum temperature for light produc- 

 tion, develops a race which emits light at this 

 temperature. Ether to the amount of .1 per 

 cent, in the ciilture media at once destroys 

 light emission, but not the life nor growth of 

 the bacteria. If the bacteria are grown for a 

 number of generations subject to the effect 

 •of .1 per cent, ether in culture, they develop 

 a race which gives forth a light fully as bright 

 if not more brilliant than normally occurs. 



The nutrition of these bacteria is of excep- 

 tional interest. It was found that a consider- 

 able amount of either a sodium salt or a 

 magnesium salt was essential to growth and 

 to light emission. The amount required for 

 light production was greater than that re- 

 quired for life. Sodium and magnesium are 

 best utilized in the form of their chlorides or 

 nitrates. Other salts of these elements can 

 be utilized, but not to the same advantage as 

 those mentioned. Salts of the other alkali 

 and all^aline-earth metals cannot replace sodi- 

 um. 



Dr. McKenney's conclusion was that the 

 light production was an intracellular phe- 

 nomenon. He held, however, that this did not 

 necessarily mean that light production was 

 inseparably bound up with life and incapable 

 of explanation on a physico-chemical basis. 

 The observations of Eodziszewski were cited 



as evidence of a possible physico-chemical ex- 

 planation. 



Mr. Frederick V. Coville spoke on the 

 ' Plants of the Klamath Indians.' He stated 

 that the country inhabited by these Indians 

 was situated where the wooded western region 

 extended upward and into the plains country 

 east of the Sierras, and that favorable sur- 

 roundings had made this tribe decidedly su- 

 perior to their neighbors. The speaker dwelt 

 at some length on the Indian names for the 

 plants, stating that the origin of many was 

 obscure, as they were not derived from roots 

 of other words, but were used only for this 

 class of names. Mr. Coville then described 

 some of the plants most extensively used and 

 stated that the Indians distinguished the 

 plants by their properties rather than by bo- 

 tanical characters. Thus they recognized the 

 differences between two very similar species of 

 Cornus, while they had but two names for 

 several species of willows. 



F. A. Lucas. 



THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 



The 555th regular meeting was held Octo- 

 ber 11, 1902, President Eathbun in the chair. 



Mr. J. F. Hayford gave a brief account of 

 recent gravity experiments at the North 

 Tamarack Mine, Michigan, in which he had 

 assisted, and spoke of the anomalous plumb- 

 line divergences and the failure of steel balls 

 dropped down the 4,600-foot shaft to reach 

 the bottom. 



The first regular paper was by Professor F. 

 W. Clarke on ' A New Law in Thermochem- 

 istry.' 



This paper is an extension of one which 

 was presented at the Pittsburgh meeting of 

 the American Association for the Advance- 

 ment of Science, and of which an abstract 

 appeared in Science for August 22. The gen- 

 eral conclusions are as follows : 



1. The absolute heat of formation of any 

 chemical compound is a function of the num- 

 ber of atomic linlvings or unions in the mole- 

 ciile. 



2. In the group of substances represented by 

 the aliphatic hydrocarbons, their halides, sul- 

 phides, amines and ethers, the absolute heat 



