Mat U, 1915] 



SCIENCE 



727 



waters of the gulf lias been built up pari passu 

 with a subsidence of the region, bringing the 

 lake floor below sea-level. This view, though 

 championed with moderation, is pretty strongly- 

 buttressed by evidence. It is, however, evident 

 that more work may profitably be directed to 

 the problem. 



It may be noted in passing that the recent 

 flooding of a portion of the alkaline playa soil 

 has not materially altered its salt content. 

 If leaching out has occurred, the evaporation 

 from the newly exposed lake floor has restored 

 the salts to the soil. 



The general position based upon geologic 

 evidence taken by Mr. Free receives additional 

 support from the study of the nature and 

 amount of salinity by Dr. W. H. Eoss, who 

 finds that the concentrations and solid com- 

 ponents of the Salton Sea to be such as to 

 indicate an originally fresh-water body. 



The increasing concentration of these vari- 

 ous solutes is found by Dr. A. E. Vinson not 

 to have proceeded at equal rates for all. The 

 potassium-sodium ratio has changed, the for- 

 mer element having remained relatively con- 

 stant while the concentrations of calcium and 

 magnesium have increased at slower rates. 

 The latter fact is explained by the formation 

 of travertine, the composition of which is 

 largely of the salts (carbonate and sulfate) of 

 those elements. 



The following paper on the behavior of 

 organisms in brine, by Professor G. J. Peirce 

 is introduced, aside from its intrinsic merit, 

 evidently by reason of its future relevancy to 

 expected conditions in the Salton Sea, as eva- 

 poration proceeds to the production of a maxi- 

 mum concentration of solutes. 



Por a single instance, it will be important to 

 follow the racial history of the bacteria which 

 are the agents of cellulose hydrolyses in sub- 

 mersed plant tissues, as shown in another 

 paper by Dr. M. A. Brannon to occur as agents 

 of disintegration in the Salton waters. The 

 increasing salinity of these waters offers a suc- 

 cession of barriers beyond which only those 

 forms which possess suitable capabilities of 

 physiological adjustment may pass. It is obvi- 

 ously important to determine these capabilities. 



The subjects for Dr. Peirce's study were 



found in the salt ponds on San Francisco Bay. 

 A lively impression of the wide adaptability 

 of the living organism is had from the persist- 

 ence of numerous minute green algae and bac- 

 teria which inhabit their waters at whatever 

 concentrations. Of these a chromogenic bac- 

 terium responsible for the red coloration of 

 salted codfish, has been isolated and shown 

 to be the cause of the color of the brine and 

 salt. It will come as a shock to those who have 

 supposed a complete preservation to be effected 

 by salting to know that decay may still proceed 

 in fish saturated with salt if exposed to humid 

 air and a moderate temperature. The fluctua- 

 tions in concentration and composition of the 

 waters of " pickle ponds " and salterns strongly 

 umbrate the theory of balance in solutions, 

 since it is difficult to believe that such rela- 

 tions can here obtain. It was also found that 

 cell division in the protophytes varies inversely 

 to the concentration, being halted by the 

 higher, and stimulated by a lowering. 



The deposits of tufa which characterize most 

 markedly a vertical zone 200 feet deep, limited 

 above by the major beach line of Blake Sea, 

 were studied by Dr. J. Claude T. Jones, who 

 shows conclusively its origin to be in the activ- 

 ity of minute algse vegetation (Calothrix sp.). 

 By a method not yet understood, certain organ- 

 isms, e. g.^ Ohara, caused the calcium salts to 

 be thrown out of solution in their immediate 

 neighborhood. When the organisms are 

 minute and very numerous a quasi continuous 

 material (sinter) is formed, found however to 

 possess a structure which may be regarded, in 

 a rough sense, as coralline. Imbedded in the 

 tufa of the Salton are found snail shells. Here 

 therefore is further evidence of the fresh- 

 water character of the Blake Sea. The study 

 of tufas on the slopes of ancient lakes must 

 reveal much sure information of their previ- 

 ous history. 



Mr. S. B. Parish contributes a paper on the 

 "Plant Ecology and Floristics of the Salton 

 Sink." His long previous acquaintance with 

 the flora of the southwestern deserts places 

 him in a position to offer a particularly com- 

 plete statistical study of that portion of it in- 

 cluded in the region in question. Of 202 spe- 

 cies listed, 48 are introduced, and of these it is 



