Department of Plant Physiology. lix 



The remarkable development of the graduate work was unex- 

 pected, and the facilities of the Department were severely taxed 

 to accommodate these students. Since the department has not 

 come into the possession of the additional space expected, it may 

 be necessary to restrict the registration of minors during 1909-10. 



The changes which have been made in the course of instruction 

 in the college permitting students during the s.ocond year to (lect 

 Plant Pliysiology on the same basis as Animal or Human Physio- 

 logy may result in a considerable incren^e in courses 7(b) (now 

 7a) and 8(a). The space at the dispos-^l of the Department has 

 necessitated placing at twenty the number which tlie Department 

 will attempt to accommodate in these courses ; in fact, in order 

 to accommodate that number it is hoped to make temporary ar- 

 rangements until head house space in the new greenhouses is 

 available. 



The development of the teaching work has been most satisfactory 

 under the conditions indicated. 



II INVESTIGATION. 



Several new lines of research have been undertaken and others 

 outlined in the last report have been pushed as rapidly as the 

 facilities would permit. Some of the important topics now under 

 consideration are the following: 



(a) Nutrition Studies. An attempt is being made to secure a 

 very complete record of the action of nutrient solutions of diltcrent 

 composition upon plant growth. The antidotmg or antag;nisdc 

 action of the different constituents is being carefully v;o^ke;l out 

 in water cultures and in pot experiments; and sone unexpected 

 results have been secured. The physiological action of solutions 

 from special soil types is being determined with a view to a later 

 comparison of the effects of different salts in modifying this action. 

 Greenhouse space for this work has been wholly insufficient, and it 

 is hoped that the new greenhouses will permit the rapid develop- 

 ment and extension of this important line. 



(b) Observations on environmental factors have been continued, 

 especially in connection with the shade tent investigations; but the 

 number of recording instruments available for this type of work 

 restrict its present importance. The shade tent observations have 

 been continued for two years and a special report will be trans- 

 mittcfl which will, it is hoped, throw some light upon the action 

 of the different factors of growth, 



