424 



SCIENCE 



[N. S. Vol. XXXIX. No. 1003 



tivity of the yeast cell or its zymase is greatly 

 accelerated by the presence of these substances. 

 The question then may properly be asked 

 whether soluble phosphates do or do not accel- 

 erate the activity of the organisms or the 

 enzymes responsible for those important soil 

 processes mentioned above, and further 

 whether sulphates efiect in the same degree 

 such accelerations. 



Work in this and other laboratories has 

 progressed far enough to indicate that soluble 

 phosphates have a very material effect in in- 

 creasing the number and consequently the rate 

 of ammonification, nitrification, nitrogen fixa- 

 tion, and carbon dioxide output of those soil 

 organisms capable of carrying out these proc- 

 esses, while sulphates do not, at least in the 

 same degree, accelerate their multiplication. 

 My thanks are due Professor C. Hoffmann 

 for conducting such experiments. 



From such results it is evident that sul- 

 phates will not be of the same importance in 

 increasing crop production as can be expected 

 from the phosphates. An adequate supply of 

 sulphates is, of course, necessary, and for those 

 crops making an abundant use of sulphur, 

 such as the high protein plants and the mem- 

 bers of the Cruciferse, a further concentration 

 in sulphates of the soil water may often result 

 in increased crop production. But to the phos- 

 phates must be ascribed functions additional 

 to that of merely maintaining a certain con- 

 centration of phosphorus in the soil solution — 

 namely, the important function of greatly 

 accelerating the biological activities of the 

 soil. 



In conclusion, however, it should be empha- 

 sized that as crop production per unit of area 

 increases through the extended use of added 

 phosphorus and attention to proper soil reac- 

 tion, there will result an increased demand 

 for sulphur. E. B. Hart 



University of Wisconsin 



GRIZZLY bears: skulls wanted 



Half a century ago a considerable number 



of wholly distinct species of grizzly bears 



inhabited the western part of North America. 



They ranged from the eastern edge of the 



Great Plains in Manitoba and the Dakotas 

 westerly to the Pacific coast in British Colum- 

 bia and California, and from the shores of the 

 Arctic ocean south into Mexico. The species 

 inhabiting Alaska and the western provinces 

 of Canada, though reduced in numbers, may 

 still be counted among the living, but those of 

 the western United States are with few excep- 

 tions extinct; and what is still worse, in most 

 cases only a few skulls remain to afford future 

 students a fragmentary and imperfect picture 

 of the great carnivores which not long ago 

 were dominant figures in our wild life. 



For twenty-three years I have been engaged 

 in a study of the bears, and have been favored 

 with specimens (mainly skulls) from nearly 

 all the museums and private collections of the 

 IJnited States and Canada. Still, owing to 

 wide gaps in this material, many questions 

 have arisen which can not be answered. Not 

 only is it impossible to map the ranges of the 

 different species with anything like precision, 

 but in some cases, owing to the absence of 

 skulls of adult males, the characters which 

 serve to distinguish one species from another 

 can be determined only in part. 



Therefore, in the hope of obtaining more 

 light on some of these questions before going 

 to press, I wish to make a final appeal to all 

 who have skulls of grizzlies in their possession. 

 I am anxious to see as many skulls as possible 

 of both sexes from all parts of the western 

 United States, British Columbia, Alberta, 

 Manitoba, Tukon Territory and Alaska, and 

 would like to purchase or borrow all that I 

 have not already seen. Owners of skulls will 

 confer a favor by addressing 



C. Hart Merriam 

 National Museum, 

 Washington, D. C. 



QUOTATIONS 



THE PARTICIPATION OP UNIVERSITY PROFESSORS 



IN POLITICS ^ 



My dear President McVey: I regret to 

 advise you that I find myself out of harmony 



1 Correspondence between the professor of law 

 and the president of the "University of North Da- 

 kota. 



