May 22, 1914] 



SCIENCE 



769 



tion within a few days. In March, however, it re- 

 appeared and grew well. Desmids, such as Coz- 

 marium, Clostermm and Micrasterias, as well as 

 Mougeotia, Vlothrix and Stigeolonium, which were 

 collected in the spore stage, germinated and grew 

 readily at a temperature of 20° C. Spirogyra, 

 Vaucheria and Cladaphora were most successfully 

 grown at a temperature of 5° C. or less. The ma- 

 jority of the Chlorophj'CEe collected grew vigor- 

 ously in city water, provided that the tempera- 

 ture was between 5° C. and 20° 0. Vaucheria, 

 Scenodesmus and other Protoeoccaceffi flourished 

 throughout the year. CEdogonimn and Clia;to- 

 pliora developed freely towards spring. Diatoms, 

 such as Navicula, were plentiful at low tempera- 

 tures. By periodically renewing the water to pre- 

 vent the concentration of the mineral contents and 

 by guarding against excessive exposure to strong 

 light, many aquaria were kept in good condition 

 during the following summer and supplied much 

 material used for class- work throughout the winter 

 of 1912-13. Towards spring, in 1913, Scenodes- 

 mus and a few other types crowded out less re- 

 sistive groups, and the cultures were allowed to 

 die during the summer of 1913. 



Alg£e similarly treated in the autumn of 1913 

 have not developed well. The summer was unfa- 

 vorable to the majority and they were not in good 

 condition when collected. Spirogyra and other 

 Conjugate, several of the ProtococeaceEB and 

 (Edogoiimm began to grow after a few weeks. 

 But in December, practically all of the aquaria 

 contained species of Bacillus, Spirillum and 

 Vibrio, as well as one or two water molds. Sev- 

 eral factors probably contributed to this result. 

 A less rigorous use of hypochlorite of lime in the 

 treatment of the city water was suggested as a 

 partial explanation by Dr. Adami during the dis- 

 cussion which followed the reading of the paper. 

 It is obvious that when water-supplies are freed 

 from bacteria by means of hypochlorite of lime, 

 such a free development of algas is permitted as to 

 require treatment by copper sulphate or other 

 measures to prevent pollution. 

 Toxic Products in Food and Their Detection: 



Chas. H. Higgins. 



Outline of necessity for the formulation of a 

 method which could be used as a standard in 

 routine examinations connected with the adminis- 

 tration of the Meat and Canned Foods Act. 



Three forms of poisoning in meat food products 

 recorded by Edelmann. These are: (1) poison- 

 ing resulting from an infection by the Bacillus 

 enteritidis (Gartner); (2) poisoning resulting 



from the toxic products of the Bacterium coli, 

 proteus species, etc., (3) poisoning resulting from 

 the Bacillus botulinus. These food poisonings are 

 the result of a direct bacterial infection or the 

 poisoning from toxic products formed during their 

 growth. Methods of detection are bacterial, such 

 as Rosenau's, the hoiling test, judgment depend- 

 ing upon the odor and the various feeding tests, 

 principally with mice. None of these meet the re- 

 quirements of routine examinations, as the indi- 

 vidual element is an important factor and one that 

 can not be standardized. The method employed 

 is through the preparation of a solution of the 

 material under consideration; in the case of com- 

 mercial gelatines a ten per cent, solution, and fol- 

 lowing the method of Bosenau injecting this sub- 

 cutaneously in amounts of 1 e.c. to 10 e.c, which 

 contain from 0.1 to 1.0 of the original gelatine. 

 For other meat food products the method is similar 

 save that the food is leached with normal saline or 

 distilled water, either proving equally satisfactory. 

 In every case ten guinea-pigs are used, preferably 

 of 250 grams weight, these having been shown 

 to be most suitable for this purpose. 



This method was used on upwards of two hun- 

 dred samples. In one instance untoward effect oc- 

 euring in sixteen persons, was directly traced to 

 gelatine entering food product. In other cases un- 

 toward effect was found to be due to faulty meth- 

 ods of handling. 



Proteid products have not interfered with the 

 results and have not led to uncontrollable factors. 

 Judgment depends upon the presence of illness or 

 death among the inoculated animals. Period of 

 observation, five days. 



A. Parker Kitchens, 



Secretary 

 (To he continued) 



SOCIETIES AND ACADEMIES 



THE AMERICAN MATHEMATICAL SOCIETY 



The one hundred and seventieth regular meet- 

 ing of the society was held at Ck)lumbia Univer- 

 sity on Saturday, April 25. The attendance at 

 the morning and afternoon sessions included forty- 

 four members. Ex-president BOcher occupied the 

 chair, being relieved by Vice-president Eisenhart, 

 Ex-president Fiske and Professor Tyler. The 

 council announced the election of the following 

 persons to membership in the society: Dr. T. H. 

 Brown, Yale University; Dr. Josephine E. Burns, 

 University of Illinois; Professor C. P. Gummer, 

 Queen's University, Kingston, Ontario; Mr. G. 



